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• ubuntu 12.04 python problem or?

  - by Trki

  Hi i am trying to fix this for a long time but without success. When i open my zsh terminal i get this error: (terminal is working but error appear) Welcome to the world of tomorrow! virtualenvwrapper_run_hook:12: permission denied: virtualenvwrapper.sh: There was a problem running the initialization hooks. If Python could not import the module virtualenvwrapper.hook_loader, check that virtualenv has been installed for VIRTUALENVWRAPPER_PYTHON= and that PATH is set properly. I tried few things but... dont know how to solve it. Somehow during looking for a search i found i should post here an output of: ? sudo dpkg --configure -a Setting up python-pip (1.0-1build1) ... /var/lib/dpkg/info/python-pip.postinst: 6: /var/lib/dpkg/info/python-pip.postinst: pycompile: not found dpkg: error processing python-pip (--configure): subprocess installed post-installation script returned error exit status 127 Setting up libc-dev-bin (2.15-0ubuntu10.5) ... Setting up gnome-control-center-data (1:3.4.2-0ubuntu0.13) ... Setting up linux-libc-dev (3.2.0-56.86) ... Setting up python-virtualenv (1.7.1.2-1) ... /var/lib/dpkg/info/python-virtualenv.postinst: 6: /var/lib/dpkg/info/python-virtualenv.postinst: pycompile: not found dpkg: error processing python-virtualenv (--configure): subprocess installed post-installation script returned error exit status 127 Setting up libglib2.0-0 (2.32.4-0ubuntu1) ... Setting up libglib2.0-0:i386 (2.32.4-0ubuntu1) ... Setting up gimp (2.6.12-1ubuntu1.2) ... /var/lib/dpkg/info/gimp.postinst: 11: /var/lib/dpkg/info/gimp.postinst: pycompile: not found dpkg: error processing gimp (--configure): subprocess installed post-installation script returned error exit status 127 Setting up libpolkit-gobject-1-0 (0.104-1ubuntu1.1) ... Setting up libgnome-control-center1 (1:3.4.2-0ubuntu0.13) ... Setting up libnm-util2 (0.9.4.0-0ubuntu4.3) ... Setting up libc6-dev (2.15-0ubuntu10.5) ... Setting up libpulse-mainloop-glib0 (1:1.1-0ubuntu15.4) ... dpkg: dependency problems prevent configuration of virtualenvwrapper: virtualenvwrapper depends on python-virtualenv; however: Package python-virtualenv is not configured yet. dpkg: error processing virtualenvwrapper (--configure): dependency problems - leaving unconfigured Setting up libpolkit-agent-1-0 (0.104-1ubuntu1.1) ... Setting up libupower-glib1 (0.9.15-3git1ubuntu0.1) ... Setting up libaccountsservice0 (0.6.15-2ubuntu9.6.1) ... Setting up libpolkit-backend-1-0 (0.104-1ubuntu1.1) ... Setting up libglib2.0-bin (2.32.4-0ubuntu1) ... Setting up libnm-glib4 (0.9.4.0-0ubuntu4.3) ... Setting up policykit-1 (0.104-1ubuntu1.1) ... Setting up gnome-settings-daemon (3.4.2-0ubuntu0.6.4) ... Setting up accountsservice (0.6.15-2ubuntu9.6.1) ... dpkg: error processing ubuntu-system-service (--configure): Package is in a very bad inconsistent state - you should reinstall it before attempting configuration. Processing triggers for libc-bin ... ldconfig deferred processing now taking place Errors were encountered while processing: python-pip python-virtualenv gimp virtualenvwrapper ubuntu-system-service Also: ? python --version zsh: command not found: python Part of my ~/.zshrc # python virtual env wrapper if [ -f ~/.local/bin/virtualenvwrapper.sh ]; then export WORKON_HOME=~/.virtualenvs source ~/.local/bin/virtualenvwrapper.sh plugins=("${plugins[@]}" virtualenvwrapper) fi # pythonbrew [[ -s ~/.pythonbrew/etc/bashrc ]] && source ~/.pythonbrew/etc/bashrc Part os zsh -xv # # Invoke the initialization functions # virtualenvwrapper_initialize +/home/trki/.local/bin/virtualenvwrapper.sh:1179> virtualenvwrapper_initialize +virtualenvwrapper_initialize:1> virtualenvwrapper_derive_workon_home +virtualenvwrapper_derive_workon_home:1> typeset 'workon_home_dir=/home/trki/.virtualenvs' +virtualenvwrapper_derive_workon_home:5> [ /home/trki/.virtualenvs '=' '' ']' +virtualenvwrapper_derive_workon_home:12> echo /home/trki/.virtualenvs +virtualenvwrapper_derive_workon_home:12> unset GREP_OPTIONS +virtualenvwrapper_derive_workon_home:12> grep '^[^/~]' +virtualenvwrapper_derive_workon_home:21> echo /home/trki/.virtualenvs +virtualenvwrapper_derive_workon_home:21> unset GREP_OPTIONS +virtualenvwrapper_derive_workon_home:21> egrep '([\$~]|//)' +virtualenvwrapper_derive_workon_home:30> echo /home/trki/.virtualenvs +virtualenvwrapper_derive_workon_home:31> return 0 +virtualenvwrapper_initialize:1> export 'WORKON_HOME=/home/trki/.virtualenvs' +virtualenvwrapper_initialize:3> virtualenvwrapper_verify_workon_home -q +virtualenvwrapper_verify_workon_home:1> RC=0 +virtualenvwrapper_verify_workon_home:2> [ ! -d /home/trki/.virtualenvs/ ']' +virtualenvwrapper_verify_workon_home:11> return 0 +virtualenvwrapper_initialize:6> [ /home/trki/.virtualenvs '=' '' ']' +virtualenvwrapper_initialize:11> virtualenvwrapper_run_hook initialize +virtualenvwrapper_run_hook:1> typeset hook_script +virtualenvwrapper_run_hook:2> typeset result +virtualenvwrapper_run_hook:4> hook_script=+virtualenvwrapper_run_hook:4> virtualenvwrapper_tempfile initialize-hook +virtualenvwrapper_tempfile:2> typeset 'suffix=initialize-hook' +virtualenvwrapper_tempfile:3> typeset file +virtualenvwrapper_tempfile:5> file=+virtualenvwrapper_tempfile:5> virtualenvwrapper_mktemp -t virtualenvwrapper-initialize-hook-XXXXXXXXXX +virtualenvwrapper_mktemp:1> mktemp -t virtualenvwrapper-initialize-hook-XXXXXXXXXX +virtualenvwrapper_tempfile:5> file=/tmp/virtualenvwrapper-initialize-hook-OhY86PXmo7 +virtualenvwrapper_tempfile:6> [ 0 -ne 0 ']' +virtualenvwrapper_tempfile:6> [ -z /tmp/virtualenvwrapper-initialize-hook-OhY86PXmo7 ']' +virtualenvwrapper_tempfile:6> [ ! -f /tmp/virtualenvwrapper-initialize-hook-OhY86PXmo7 ']' +virtualenvwrapper_tempfile:11> echo /tmp/virtualenvwrapper-initialize-hook-OhY86PXmo7 +virtualenvwrapper_tempfile:12> return 0 +virtualenvwrapper_run_hook:4> hook_script=/tmp/virtualenvwrapper-initialize-hook-OhY86PXmo7 +virtualenvwrapper_run_hook:11> cd /home/trki/.virtualenvs +cd:1> [[ x/home/trki/.virtualenvs == x... ]] +cd:3> [[ x/home/trki/.virtualenvs == x.... ]] +cd:5> [[ x/home/trki/.virtualenvs == x..... ]] +cd:7> [[ x/home/trki/.virtualenvs == x...... ]] +cd:9> [ -d /home/trki/.autoenv ']' +cd:13> cd /home/trki/.virtualenvs +virtualenvwrapper_run_hook:12> '' -m virtualenvwrapper.hook_loader --script /tmp/virtualenvwrapper-initialize-hook-OhY86PXmo7 initialize virtualenvwrapper_run_hook:12: permission denied: +virtualenvwrapper_run_hook:15> result=126 +virtualenvwrapper_run_hook:17> [ 126 -eq 0 ']' +virtualenvwrapper_run_hook:27> [ initialize '=' initialize ']' +virtualenvwrapper_run_hook:29> cat - virtualenvwrapper.sh: There was a problem running the initialization hooks. If Python could not import the module virtualenvwrapper.hook_loader, check that virtualenv has been installed for VIRTUALENVWRAPPER_PYTHON= and that PATH is set properly. +virtualenvwrapper_run_hook:38> rm -f /tmp/virtualenvwrapper-initialize-hook-OhY86PXmo7 +virtualenvwrapper_run_hook:39> return 126 +virtualenvwrapper_initialize:13> virtualenvwrapper_setup_tab_completion +virtualenvwrapper_setup_tab_completion:1> [ -n '' ']' +virtualenvwrapper_setup_tab_completion:20> [ -n 4.3.17 ']' +virtualenvwrapper_setup_tab_completion:30> compctl -K _virtualenvs workon rmvirtualenv cpvirtualenv showvirtualenv +virtualenvwrapper_setup_tab_completion:31> compctl -K _cdvirtualenv_complete cdvirtualenv +virtualenvwrapper_setup_tab_completion:32> compctl -K _cdsitepackages_complete cdsitepackages +virtualenvwrapper_initialize:15> return 0 +/home/trki/.zshrc:17> plugins=( git python django symfony2 zsh-syntax-highlighting composer history-substring-search virtualenvwrapper ) # pythonbrew [[ -s ~/.pythonbrew/etc/bashrc ]] && source ~/.pythonbrew/etc/bashrc +/home/trki/.zshrc:21> [[ -s /home/trki/.pythonbrew/etc/bashrc ]] Also when i try to open ubuntu software center absolutly nothing happens. No idea what to do now.

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• 6 Ways to Free Up Hard Drive Space Used by Windows System Files

  - by Chris Hoffman

  We’ve previously covered the standard ways to free up space on Windows. But if you have a small solid-state drive and really want more hard space, there are geekier ways to reclaim hard drive space. Not all of these tips are recommended — in fact, if you have more than enough hard drive space, following these tips may actually be a bad idea. There’s a tradeoff to changing all of these settings. Erase Windows Update Uninstall Files Windows allows you to uninstall patches you install from Windows Update. This is helpful if an update ever causes a problem — but how often do you need to uninstall an update, anyway? And will you really ever need to uninstall updates you’ve installed several years ago? These uninstall files are probably just wasting space on your hard drive. A recent update released for Windows 7 allows you to erase Windows Update files from the Windows Disk Cleanup tool. Open Disk Cleanup, click Clean up system files, check the Windows Update Cleanup option, and click OK. If you don’t see this option, run Windows Update and install the available updates. Remove the Recovery Partition Windows computers generally come with recovery partitions that allow you to reset your computer back to its factory default state without juggling discs. The recovery partition allows you to reinstall Windows or use the Refresh and Reset your PC features. These partitions take up a lot of space as they need to contain a complete system image. On Microsoft’s Surface Pro, the recovery partition takes up about 8-10 GB. On other computers, it may be even larger as it needs to contain all the bloatware the manufacturer included. Windows 8 makes it easy to copy the recovery partition to removable media and remove it from your hard drive. If you do this, you’ll need to insert the removable media whenever you want to refresh or reset your PC. On older Windows 7 computers, you could delete the recovery partition using a partition manager — but ensure you have recovery media ready if you ever need to install Windows. If you prefer to install Windows from scratch instead of using your manufacturer’s recovery partition, you can just insert a standard Window disc if you ever want to reinstall Windows. Disable the Hibernation File Windows creates a hidden hibernation file at C:\hiberfil.sys. Whenever you hibernate the computer, Windows saves the contents of your RAM to the hibernation file and shuts down the computer. When it boots up again, it reads the contents of the file into memory and restores your computer to the state it was in. As this file needs to contain much of the contents of your RAM, it’s 75% of the size of your installed RAM. If you have 12 GB of memory, that means this file takes about 9 GB of space. On a laptop, you probably don’t want to disable hibernation. However, if you have a desktop with a small solid-state drive, you may want to disable hibernation to recover the space. When you disable hibernation, Windows will delete the hibernation file. You can’t move this file off the system drive, as it needs to be on C:\ so Windows can read it at boot. Note that this file and the paging file are marked as “protected operating system files” and aren’t visible by default. Shrink the Paging File The Windows paging file, also known as the page file, is a file Windows uses if your computer’s available RAM ever fills up. Windows will then “page out” data to disk, ensuring there’s always available memory for applications — even if there isn’t enough physical RAM. The paging file is located at C:\pagefile.sys by default. You can shrink it or disable it if you’re really crunched for space, but we don’t recommend disabling it as that can cause problems if your computer ever needs some paging space. On our computer with 12 GB of RAM, the paging file takes up 12 GB of hard drive space by default. If you have a lot of RAM, you can certainly decrease the size — we’d probably be fine with 2 GB or even less. However, this depends on the programs you use and how much memory they require. The paging file can also be moved to another drive — for example, you could move it from a small SSD to a slower, larger hard drive. It will be slower if Windows ever needs to use the paging file, but it won’t use important SSD space. Configure System Restore Windows seems to use about 10 GB of hard drive space for “System Protection” by default. This space is used for System Restore snapshots, allowing you to restore previous versions of system files if you ever run into a system problem. If you need to free up space, you could reduce the amount of space allocated to system restore or even disable it entirely. Of course, if you disable it entirely, you’ll be unable to use system restore if you ever need it. You’d have to reinstall Windows, perform a Refresh or Reset, or fix any problems manually. Tweak Your Windows Installer Disc Want to really start stripping down Windows, ripping out components that are installed by default? You can do this with a tool designed for modifying Windows installer discs, such as WinReducer for Windows 8 or RT Se7en Lite for Windows 7. These tools allow you to create a customized installation disc, slipstreaming in updates and configuring default options. You can also use them to remove components from the Windows disc, shrinking the size of the resulting Windows installation. This isn’t recommended as you could cause problems with your Windows installation by removing important features. But it’s certainly an option if you want to make Windows as tiny as possible. Most Windows users can benefit from removing Windows Update uninstallation files, so it’s good to see that Microsoft finally gave Windows 7 users the ability to quickly and easily erase these files. However, if you have more than enough hard drive space, you should probably leave well enough alone and let Windows manage the rest of these settings on its own. Image Credit: Yutaka Tsutano on Flickr     

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• C#: LINQ vs foreach - Round 1.

  - by James Michael Hare

  So I was reading Peter Kellner's blog entry on Resharper 5.0 and its LINQ refactoring and thought that was very cool.  But that raised a point I had always been curious about in my head -- which is a better choice: manual foreach loops or LINQ?    The answer is not really clear-cut.  There are two sides to any code cost arguments: performance and maintainability.  The first of these is obvious and quantifiable.  Given any two pieces of code that perform the same function, you can run them side-by-side and see which piece of code performs better.   Unfortunately, this is not always a good measure.  Well written assembly language outperforms well written C++ code, but you lose a lot in maintainability which creates a big techncial debt load that is hard to offset as the application ages.  In contrast, higher level constructs make the code more brief and easier to understand, hence reducing technical cost.   Now, obviously in this case we're not talking two separate languages, we're comparing doing something manually in the language versus using a higher-order set of IEnumerable extensions that are in the System.Linq library.   Well, before we discuss any further, let's look at some sample code and the numbers.  First, let's take a look at the for loop and the LINQ expression.  This is just a simple find comparison:       // find implemented via LINQ     public static bool FindViaLinq(IEnumerable<int> list, int target)     {         return list.Any(item => item == target);     }         // find implemented via standard iteration     public static bool FindViaIteration(IEnumerable<int> list, int target)     {         foreach (var i in list)         {             if (i == target)             {                 return true;             }         }           return false;     }   Okay, looking at this from a maintainability point of view, the Linq expression is definitely more concise (8 lines down to 1) and is very readable in intention.  You don't have to actually analyze the behavior of the loop to determine what it's doing.   So let's take a look at performance metrics from 100,000 iterations of these methods on a List<int> of varying sizes filled with random data.  For this test, we fill a target array with 100,000 random integers and then run the exact same pseudo-random targets through both searches.                       List<T> On 100,000 Iterations     Method      Size     Total (ms)  Per Iteration (ms)  % Slower     Any         10       26          0.00046             30.00%     Iteration   10       20          0.00023             -     Any         100      116         0.00201             18.37%     Iteration   100      98          0.00118             -     Any         1000     1058        0.01853             16.78%     Iteration   1000     906         0.01155             -     Any         10,000   10,383      0.18189             17.41%     Iteration   10,000   8843        0.11362             -     Any         100,000  104,004     1.8297              18.27%     Iteration   100,000  87,941      1.13163             -   The LINQ expression is running about 17% slower for average size collections and worse for smaller collections.  Presumably, this is due to the overhead of the state machine used to track the iterators for the yield returns in the LINQ expressions, which seems about right in a tight loop such as this.   So what about other LINQ expressions?  After all, Any() is one of the more trivial ones.  I decided to try the TakeWhile() algorithm using a Count() to get the position stopped like the sample Pete was using in his blog that Resharper refactored for him into LINQ:       // Linq form     public static int GetTargetPosition1(IEnumerable<int> list, int target)     {         return list.TakeWhile(item => item != target).Count();     }       // traditionally iterative form     public static int GetTargetPosition2(IEnumerable<int> list, int target)     {         int count = 0;           foreach (var i in list)         {             if(i == target)             {                 break;             }               ++count;         }           return count;     }   Once again, the LINQ expression is much shorter, easier to read, and should be easier to maintain over time, reducing the cost of technical debt.  So I ran these through the same test data:                       List<T> On 100,000 Iterations     Method      Size     Total (ms)  Per Iteration (ms)  % Slower     TakeWhile   10       41          0.00041             128%     Iteration   10       18          0.00018             -     TakeWhile   100      171         0.00171             88%     Iteration   100      91          0.00091             -     TakeWhile   1000     1604        0.01604             94%     Iteration   1000     825         0.00825             -     TakeWhile   10,000   15765       0.15765             92%     Iteration   10,000   8204        0.08204             -     TakeWhile   100,000  156950      1.5695              92%     Iteration   100,000  81635       0.81635             -     Wow!  I expected some overhead due to the state machines iterators produce, but 90% slower?  That seems a little heavy to me.  So then I thought, well, what if TakeWhile() is not the right tool for the job?  The problem is TakeWhile returns each item for processing using yield return, whereas our for-loop really doesn't care about the item beyond using it as a stop condition to evaluate. So what if that back and forth with the iterator state machine is the problem?  Well, we can quickly create an (albeit ugly) lambda that uses the Any() along with a count in a closure (if a LINQ guru knows a better way PLEASE let me know!), after all , this is more consistent with what we're trying to do, we're trying to find the first occurence of an item and halt once we find it, we just happen to be counting on the way.  This mostly matches Any().       // a new method that uses linq but evaluates the count in a closure.     public static int TakeWhileViaLinq2(IEnumerable<int> list, int target)     {         int count = 0;         list.Any(item =>             {                 if(item == target)                 {                     return true;                 }                   ++count;                 return false;             });         return count;     }     Now how does this one compare?                         List<T> On 100,000 Iterations     Method         Size     Total (ms)  Per Iteration (ms)  % Slower     TakeWhile      10       41          0.00041             128%     Any w/Closure  10       23          0.00023             28%     Iteration      10       18          0.00018             -     TakeWhile      100      171         0.00171             88%     Any w/Closure  100      116         0.00116             27%     Iteration      100      91          0.00091             -     TakeWhile      1000     1604        0.01604             94%     Any w/Closure  1000     1101        0.01101             33%     Iteration      1000     825         0.00825             -     TakeWhile      10,000   15765       0.15765             92%     Any w/Closure  10,000   10802       0.10802             32%     Iteration      10,000   8204        0.08204             -     TakeWhile      100,000  156950      1.5695              92%     Any w/Closure  100,000  108378      1.08378             33%     Iteration      100,000  81635       0.81635             -     Much better!  It seems that the overhead of TakeAny() returning each item and updating the state in the state machine is drastically reduced by using Any() since Any() iterates forward until it finds the value we're looking for -- for the task we're attempting to do.   So the lesson there is, make sure when you use a LINQ expression you're choosing the best expression for the job, because if you're doing more work than you really need, you'll have a slower algorithm.  But this is true of any choice of algorithm or collection in general.     Even with the Any() with the count in the closure it is still about 30% slower, but let's consider that angle carefully.  For a list of 100,000 items, it was the difference between 1.01 ms and 0.82 ms roughly in a List<T>.  That's really not that bad at all in the grand scheme of things.  Even running at 90% slower with TakeWhile(), for the vast majority of my projects, an extra millisecond to save potential errors in the long term and improve maintainability is a small price to pay.  And if your typical list is 1000 items or less we're talking only microseconds worth of difference.   It's like they say: 90% of your performance bottlenecks are in 2% of your code, so over-optimizing almost never pays off.  So personally, I'll take the LINQ expression wherever I can because they will be easier to read and maintain (thus reducing technical debt) and I can rely on Microsoft's development to have coded and unit tested those algorithm fully for me instead of relying on a developer to code the loop logic correctly.   If something's 90% slower, yes, it's worth keeping in mind, but it's really not until you start get magnitudes-of-order slower (10x, 100x, 1000x) that alarm bells should really go off.  And if I ever do need that last millisecond of performance?  Well then I'll optimize JUST THAT problem spot.  To me it's worth it for the readability, speed-to-market, and maintainability.

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• Thread placement policies on NUMA systems - update

  - by Dave

  In a prior blog entry I noted that Solaris used a "maximum dispersal" placement policy to assign nascent threads to their initial processors. The general idea is that threads should be placed as far away from each other as possible in the resource topology in order to reduce resource contention between concurrently running threads. This policy assumes that resource contention -- pipelines, memory channel contention, destructive interference in the shared caches, etc -- will likely outweigh (a) any potential communication benefits we might achieve by packing our threads more densely onto a subset of the NUMA nodes, and (b) benefits of NUMA affinity between memory allocated by one thread and accessed by other threads. We want our threads spread widely over the system and not packed together. Conceptually, when placing a new thread, the kernel picks the least loaded node NUMA node (the node with lowest aggregate load average), and then the least loaded core on that node, etc. Furthermore, the kernel places threads onto resources -- sockets, cores, pipelines, etc -- without regard to the thread's process membership. That is, initial placement is process-agnostic. Keep reading, though. This description is incorrect. On Solaris 10 on a SPARC T5440 with 4 x T2+ NUMA nodes, if the system is otherwise unloaded and we launch a process that creates 20 compute-bound concurrent threads, then typically we'll see a perfect balance with 5 threads on each node. We see similar behavior on an 8-node x86 x4800 system, where each node has 8 cores and each core is 2-way hyperthreaded. So far so good; this behavior seems in agreement with the policy I described in the 1st paragraph. I recently tried the same experiment on a 4-node T4-4 running Solaris 11. Both the T5440 and T4-4 are 4-node systems that expose 256 logical thread contexts. To my surprise, all 20 threads were placed onto just one NUMA node while the other 3 nodes remained completely idle. I checked the usual suspects such as processor sets inadvertently left around by colleagues, processors left offline, and power management policies, but the system was configured normally. I then launched multiple concurrent instances of the process, and, interestingly, all the threads from the 1st process landed on one node, all the threads from the 2nd process landed on another node, and so on. This happened even if I interleaved thread creating between the processes, so I was relatively sure the effect didn't related to thread creation time, but rather that placement was a function of process membership. I this point I consulted the Solaris sources and talked with folks in the Solaris group. The new Solaris 11 behavior is intentional. The kernel is no longer using a simple maximum dispersal policy, and thread placement is process membership-aware. Now, even if other nodes are completely unloaded, the kernel will still try to pack new threads onto the home lgroup (socket) of the primordial thread until the load average of that node reaches 50%, after which it will pick the next least loaded node as the process's new favorite node for placement. On the T4-4 we have 64 logical thread contexts (strands) per socket (lgroup), so if we launch 48 concurrent threads we will find 32 placed on one node and 16 on some other node. If we launch 64 threads we'll find 32 and 32. That means we can end up with our threads clustered on a small subset of the nodes in a way that's quite different that what we've seen on Solaris 10. So we have a policy that allows process-aware packing but reverts to spreading threads onto other nodes if a node becomes too saturated. It turns out this policy was enabled in Solaris 10, but certain bugs suppressed the mixed packing/spreading behavior. There are configuration variables in /etc/system that allow us to dial the affinity between nascent threads and their primordial thread up and down: see lgrp_expand_proc_thresh, specifically. In the OpenSolaris source code the key routine is mpo_update_tunables(). This method reads the /etc/system variables and sets up some global variables that will subsequently be used by the dispatcher, which calls lgrp_choose() in lgrp.c to place nascent threads. Lgrp_expand_proc_thresh controls how loaded an lgroup must be before we'll consider homing a process's threads to another lgroup. Tune this value lower to have it spread your process's threads out more. To recap, the 'new' policy is as follows. Threads from the same process are packed onto a subset of the strands of a socket (50% for T-series). Once that socket reaches the 50% threshold the kernel then picks another preferred socket for that process. Threads from unrelated processes are spread across sockets. More precisely, different processes may have different preferred sockets (lgroups). Beware that I've simplified and elided details for the purposes of explication. The truth is in the code. Remarks: It's worth noting that initial thread placement is just that. If there's a gross imbalance between the load on different nodes then the kernel will migrate threads to achieve a better and more even distribution over the set of available nodes. Once a thread runs and gains some affinity for a node, however, it becomes "stickier" under the assumption that the thread has residual cache residency on that node, and that memory allocated by that thread resides on that node given the default "first-touch" page-level NUMA allocation policy. Exactly how the various policies interact and which have precedence under what circumstances could the topic of a future blog entry. The scheduler is work-conserving. The x4800 mentioned above is an interesting system. Each of the 8 sockets houses an Intel 7500-series processor. Each processor has 3 coherent QPI links and the system is arranged as a glueless 8-socket twisted ladder "mobius" topology. Nodes are either 1 or 2 hops distant over the QPI links. As an aside the mapping of logical CPUIDs to physical resources is rather interesting on Solaris/x4800. On SPARC/Solaris the CPUID layout is strictly geographic, with the highest order bits identifying the socket, the next lower bits identifying the core within that socket, following by the pipeline (if present) and finally the logical thread context ("strand") on the core. But on Solaris on the x4800 the CPUID layout is as follows. [6:6] identifies the hyperthread on a core; bits [5:3] identify the socket, or package in Intel terminology; bits [2:0] identify the core within a socket. Such low-level details should be of interest only if you're binding threads -- a bad idea, the kernel typically handles placement best -- or if you're writing NUMA-aware code that's aware of the ambient placement and makes decisions accordingly. Solaris introduced the so-called critical-threads mechanism, which is expressed by putting a thread into the FX scheduling class at priority 60. The critical-threads mechanism applies to placement on cores, not on sockets, however. That is, it's an intra-socket policy, not an inter-socket policy. Solaris 11 introduces the Power Aware Dispatcher (PAD) which packs threads instead of spreading them out in an attempt to be able to keep sockets or cores at lower power levels. Maximum dispersal may be good for performance but is anathema to power management. PAD is off by default, but power management polices constitute yet another confounding factor with respect to scheduling and dispatching. If your threads communicate heavily -- one thread reads cache lines last written by some other thread -- then the new dense packing policy may improve performance by reducing traffic on the coherent interconnect. On the other hand if your threads in your process communicate rarely, then it's possible the new packing policy might result on contention on shared computing resources. Unfortunately there's no simple litmus test that says whether packing or spreading is optimal in a given situation. The answer varies by system load, application, number of threads, and platform hardware characteristics. Currently we don't have the necessary tools and sensoria to decide at runtime, so we're reduced to an empirical approach where we run trials and try to decide on a placement policy. The situation is quite frustrating. Relatedly, it's often hard to determine just the right level of concurrency to optimize throughput. (Understanding constructive vs destructive interference in the shared caches would be a good start. We could augment the lines with a small tag field indicating which strand last installed or accessed a line. Given that, we could augment the CPU with performance counters for misses where a thread evicts a line it installed vs misses where a thread displaces a line installed by some other thread.)

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• My Code Kata–A Solution Kata

  - by Glav

  There are many developers and coders out there who like to do code Kata’s to keep their coding ability up to scratch and to practice their skills. I think it is a good idea. While I like the concept, I find them dead boring and of minimal purpose. Yes, they serve to hone your skills but that’s about it. They are often quite abstract, in that they usually focus on a small problem set requiring specific solutions. It is fair enough as that is how they are designed but again, I find them quite boring. What I personally like to do is go for something a little larger and a little more fun. It takes a little more time and is not as easily executed as a kata though, but it services the same purposes from a practice perspective and allows me to continue to solve some problems that are not directly part of the initial goal. This means I can cover a broader learning range and have a bit more fun. If I am lucky, sometimes they even end up being useful tools. With that in mind, I thought I’d share my current ‘kata’. It is not really a code kata as it is too big. I prefer to think of it as a ‘solution kata’. The code is on bitbucket here. What I wanted to do was create a kind of simplistic virtual world where I can create a player, or a class, stuff it into the world, and see if it survives, and can navigate its way to the exit. Requirements were pretty simple: Must be able to define a map to describe the world using simple X,Y co-ordinates. Z co-ordinates as well if you feel like getting clever. Should have the concept of entrances, exists, solid blocks, and potentially other materials (again if you want to get clever). A coder should be able to easily write a class which will act as an inhabitant of the world. An inhabitant will receive stimulus from the world in the form of surrounding environment and be able to make a decision on action which it passes back to the ‘world’ for processing. At a minimum, an inhabitant will have sight and speed characteristics which determine how far they can ‘see’ in the world, and how fast they can move. Coders who write a really bad ‘inhabitant’ should not adversely affect the rest of world. Should allow multiple inhabitants in the world. So that was the solution I set out to act as a practice solution and a little bit of fun. It had some interesting problems to solve and I figured, if it turned out ok, I could potentially use this as a ‘developer test’ for interviews. Ask a potential coder to write a class for an inhabitant. Show the coder the map they will navigate, but also mention that we will use their code to navigate a map they have not yet seen and a little more complex. I have been playing with solution for a short time now and have it working in basic concepts. Below is a screen shot using a very basic console visualiser that shows the map, boundaries, blocks, entrance, exit and players/inhabitants. The yellow asterisks ‘*’ are the players, green ‘O’ the entrance, purple ‘^’ the exit, maroon/browny ‘#’ are solid blocks. The players can move around at different speeds, knock into each others, and make directional movement decisions based on what they see and who is around them. It has been quite fun to write and it is also quite fun to develop different players to inject into the world. The code below shows a really simple implementation of an inhabitant that can work out what to do based on stimulus from the world. It is pretty simple and just tries to move in some direction if there is nothing blocking the path. public class TestPlayer:LivingEntity { public TestPlayer() { Name = "Beta Boy"; LifeKey = Guid.NewGuid(); } public override ActionResult DecideActionToPerform(EcoDev.Core.Common.Actions.ActionContext actionContext) { try { var action = new MovementAction(); // move forward if we can if (actionContext.Position.ForwardFacingPositions.Length > 0) { if (CheckAccessibilityOfMapBlock(actionContext.Position.ForwardFacingPositions[0])) { action.DirectionToMove = MovementDirection.Forward; return action; } } if (actionContext.Position.LeftFacingPositions.Length > 0) { if (CheckAccessibilityOfMapBlock(actionContext.Position.LeftFacingPositions[0])) { action.DirectionToMove = MovementDirection.Left; return action; } } if (actionContext.Position.RearFacingPositions.Length > 0) { if (CheckAccessibilityOfMapBlock(actionContext.Position.RearFacingPositions[0])) { action.DirectionToMove = MovementDirection.Back; return action; } } if (actionContext.Position.RightFacingPositions.Length > 0) { if (CheckAccessibilityOfMapBlock(actionContext.Position.RightFacingPositions[0])) { action.DirectionToMove = MovementDirection.Right; return action; } } return action; } catch (Exception ex) { World.WriteDebugInformation("Player: "+ Name, string.Format("Player Generated exception: {0}",ex.Message)); throw ex; } } private bool CheckAccessibilityOfMapBlock(MapBlock block) { if (block == null || block.Accessibility == MapBlockAccessibility.AllowEntry || block.Accessibility == MapBlockAccessibility.AllowExit || block.Accessibility == MapBlockAccessibility.AllowPotentialEntry) { return true; } return false; } } It is simple and it seems to work well. The world implementation itself decides the stimulus context that is passed to he inhabitant to make an action decision. All movement is carried out on separate threads and timed appropriately to be as fair as possible and to cater for additional skills such as speed, and eventually maybe stamina, strength, with actions like fighting. It is pretty fun to make up random maps and see how your inhabitant does. You can download the code from here. Along the way I have played with parallel extensions to make the compute intensive stuff spread across all cores, had to heavily factor in visibility of methods and properties so design of classes was paramount, work out movement algorithms that play fairly in the world and properly favour the players with higher abilities, as well as a host of other issues. So that is my ‘solution kata’. If I keep going with it, I may develop a web interface for it where people can upload assemblies and watch their player within a web browser visualiser and maybe even a map designer. What do you do to keep the fires burning?

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• Clustering for Mere Mortals (Pt 3)

  - by Geoff N. Hiten

  The Controller Now we get to the meat of the matter.  You want a virtual cluster, the first thing you have to do is create your own portable domain.  Start with a plain vanilla install of Windows 2003 R2 Standard on a semi-default VM. (1 GB RAM, 2 cores, 2 NICs, 128GB dynamically expanding VHD file).  I chose this because it had the smallest disk and memory footprint of any current supported Microsoft Server product.  I created the VM with a single dynamically expanding VHD, one fixed 16 GB VHD, and two NICs.  One NIC is connected to the outside world and the other one is part of an internal-only network.  The first NIC is set up as a DHCP client.  We will get to the other one later. I actually tried this with Windows 2008 R2, but it failed miserably.  Not sure whether it was 2008 R2 or the fact I tried to use cloned VMs in the cluster.  Clustering is one place where NewSID would really come in handy.  Too bad Microsoft bought and buried it. Load and Patch the OS (hence the need for the outside connection).This is a good time to go get dinner.  Maybe a movie too.  There are close to a hundred patches that need to be downloaded and applied.  Avoiding that mess was why I put so much time into trying to get the 2008 R2 version working.  Maybe next time.  Don’t forget to add the extensions for VMLite (or whatever virtualization product you prefer). Set a fixed IP address on the internal-only NIC.  Do not give it a gateway.  Put the same IP address for the NIC and for the DNS Server.  This IP should be in a range that is never available on your public network.  You will need all the addresses in the range available.  See the previous post for the exact settings I used. I chose 10.97.230.1 as the server.  The rest of the 10.97.230 range is what I will use later.  For the curious, those numbers are based on elements of my home address.  Not truly random, but good enough for this project. Do not bridge the network connections.  I never allowed the cluster nodes direct access to any public network. Format the fixed VHD and leave it alone for now. Promote the VM to a Domain Controller.  If you have never done this, don’t worry.  The only meaningful decision is what to call the new domain.  I prefer a bogus name that does not correspond to a real Top-Level Domain (TLD).  .com, .biz., .net, .org  are all TLDs that we know and love.  I chose .test as the TLD since it is descriptive AND it does not exist in the real world.  The domain is called MicroAD.  This gives me MicroAD.Test as my domain. During the promotion process, you will be prompted to install DNS as part of the Domain creation process.  You want to accept this option.  The installer will automatically assign this DNS server as the authoritative owner of the MicroAD.test DNS domain (not to be confused with the MicroAD.test Active Directory domain.) For the rest of the DCPROMO process, just accept the defaults. Now let’s make our IP address management easy.  Add the DHCP Role to the server.  Add the server (10.97.230.1 in this case) as the default gateway to assign to DHCP clients.  Here is where you have to be VERY careful and bind it ONLY to the Internal NIC.  Trust me, your network admin will NOT like an extra DHCP server “helping” out on her network.  Go ahead and create a range of 10-20 IP Addresses in your scope.  You might find other uses for a pocket domain controller <cough> Mirroring </cough> than just for building a cluster.  And Clustering in SQL 2008 and Windows 2008 R2 fully supports DHCP addresses. Now we have three of the five key roles ready.  Two more to go. Next comes file sharing.  Since your cluster node VMs will not have access to any outside, you have to have some way to get files into these VMs.  I simply go to the root of C: and create a “Shared” folder.  I then share it out and grant full control to “Everyone” to both the share and to the underlying NTFS folder.   This will be immensely useful for Service Packs, demo databases, and any other software that isn’t packaged as an ISO that we can mount to the VM. Finally we need to create a block-level multi-connect storage device.  The kind folks at Starwinds Software (http://www.starwindsoftware.com/) graciously gave me a non-expiring demo license for expressly this purpose.  Their iSCSI SAN software lets you create an iSCSI target from nearly any storage medium.  Refreshingly, their product does exactly what they say it does.  Thanks. Remember that 16 GB VHD file?  That is where we are going to carve into our LUNs.  I created an iSCSI folder off the root, just so I can keep everything organized.  I then carved 5 ea. 2 GB iSCSI targets from that folder.  I chose a fixed VHD for performance.  I tried this earlier with a dynamically expanding VHD, but too many layers of abstraction and sparseness combined to make it unusable even for a demo.  Stick with a fixed VHD so there is a one-to-one mapping between abstract and physical storage.  If you read the previous post, you know what I named these iSCSI LUNs and why.  Yes, I do have some left over space.  Always leave yourself room for future growth or options. This gets us up to where we can actually build the nodes and install SQL.  As with most clusters, the real work happens long before the individual nodes get installed and configured.  At least it does if you want the cluster to be a true high-availability platform.

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• Custom Model Binding of IEnumerable Properties in ASP.Net MVC 2

  - by Doug Lampe

  MVC 2 provides a GREAT feature for dealing with enumerable types.  Let's say you have an object with a parent/child relationship and you want to allow users to modify multiple children at the same time.  You can simply use the following syntax for any indexed enumerables (arrays, generic lists, etc.) and then your values will bind to your enumerable model properties. 1: <% using (Html.BeginForm("TestModelParameter", "Home")) 2: { %> 3: < table > 4: < tr >< th >ID</th><th>Name</th><th>Description</th></tr> 5: <% for (int i = 0; i < Model.Items.Count; i++) 6: { %> 7: < tr > 8: < td > 9: <%= i %> 10: </ td > 11: < td > 12: <%= Html.TextBoxFor(m => m.Items[i].Name) %> 13: </ td > 14: < td > 15: <%= Model.Items[i].Description %> 16: </ td > 17: </ tr > 18: <% } %> 19: </ table > 20: < input type ="submit" /> 21: <% } %> Then just update your model either by passing it into your action method as a parameter or explicitly with UpdateModel/TryUpdateModel. 1: public ActionResult TestTryUpdate() 2: { 3: ContainerModel model = new ContainerModel(); 4: TryUpdateModel(model); 5:   6: return View("Test", model); 7: } 8:   9: public ActionResult TestModelParameter(ContainerModel model) 10: { 11: return View("Test", model); 12: } Simple right?  Well, not quite.  The problem is the DefaultModelBinder and how it sets properties.  In this case our model has a property that is a generic list (Items).  The first bad thing the model binder does is create a new instance of the list.  This can be fixed by making the property truly read-only by removing the set accessor.  However this won't help because this behaviour continues.  As the model binder iterates through the items to "set" their values, it creates new instances of them as well.  This means you lose any information not passed via the UI to your controller so in the examplel above the "Description" property would be blank for each item after the form posts. One solution for this is custom model binding.  I have put together a solution which allows you to retain the structure of your model.  Model binding is a somewhat advanced concept so you may need to do some additional research to really understand what is going on here, but the code is fairly simple.  First we will create a binder for the parent object which will retain the state of the parent as well as some information on which children have already been bound. 1: public class ContainerModelBinder : DefaultModelBinder 2: { 3: /// <summary> 4: /// Gets an instance of the model to be used to bind child objects. 5: /// </summary> 6: public ContainerModel Model { get; private set; } 7:   8: /// <summary> 9: /// Gets a list which will be used to track which items have been bound. 10: /// </summary> 11: public List<ItemModel> BoundItems { get; private set; } 12:   13: public ContainerModelBinder() 14: { 15: BoundItems = new List<ItemModel>(); 16: } 17:   18: protected override object CreateModel(ControllerContext controllerContext, ModelBindingContext bindingContext, Type modelType) 19: { 20: // Set the Model property so child binders can find children. 21: Model = base.CreateModel(controllerContext, bindingContext, modelType) as ContainerModel; 22:   23: return Model; 24: } 25: } Next we will create the child binder and have it point to the parent binder to get instances of the child objects.  Note that this only works if there is only one property of type ItemModel in the parent class since the property to find the item in the parent is hard coded. 1: public class ItemModelBinder : DefaultModelBinder 2: { 3: /// <summary> 4: /// Gets the parent binder so we can find objects in the parent's collection 5: /// </summary> 6: public ContainerModelBinder ParentBinder { get; private set; } 7: 8: public ItemModelBinder(ContainerModelBinder containerModelBinder) 9: { 10: ParentBinder = containerModelBinder; 11: } 12:   13: protected override object CreateModel(ControllerContext controllerContext, ModelBindingContext bindingContext, Type modelType) 14: { 15: // Find the item in the parent collection and add it to the bound items list. 16: ItemModel item = ParentBinder.Model.Items.FirstOrDefault(i => !ParentBinder.BoundItems.Contains(i)); 17: ParentBinder.BoundItems.Add(item); 18: 19: return item; 20: } 21: } Finally, we will register these binders in Global.asax.cs so they will be used to bind the classes. 1: protected void Application_Start() 2: { 3: AreaRegistration.RegisterAllAreas(); 4:   5: ContainerModelBinder containerModelBinder = new ContainerModelBinder(); 6: ModelBinders.Binders.Add(typeof(ContainerModel), containerModelBinder); 7: ModelBinders.Binders.Add(typeof(ItemModel), new ItemModelBinder(containerModelBinder)); 8:   9: RegisterRoutes(RouteTable.Routes); 10: } I'm sure some of my fellow geeks will comment that this could be done more efficiently by simply rewriting some of the methods of the default model binder to get the same desired behavior.  I like my method shown here because it extends the binder class instead of modifying it so it minimizes the potential for unforseen problems. In a future post (if I ever get around to it) I will explore creating a generic version of these binders.

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• Clustering for Mere Mortals (Pt3)

  - by Geoff N. Hiten

  The Controller Now we get to the meat of the matter.  You want a virtual cluster, the first thing you have to do is create your own portable domain.  IStart with a plain vanilla install of Windows 2003 R2 Standard on a semi-default VM. (1 GB RAM, 2 cores, 2 NICs, 128GB dynamically expanding VHD file).  I chose this because it had the smallest disk and memory footprint of any current supported Microsoft Server product.  I created the VM with a single dynamically expanding VHD, one fixed 16 GB VHD, and two NICs.  One NIC is connected to the outside world and the other one is part of an internal-only network.  The first NIC is set up as a DHCP client.  We will get to the other one later. I actually tried this with Windows 2008 R2, but it failed miserably.  Not sure whether it was 2008 R2 or the fact I tried to use cloned VMs in the cluster.  Clustering is one place where NewSID would really come in handy.  Too bad Microsoft bought and buried it. Load and Patch the OS (hence the need for the outside connection).This is a good time to go get dinner.  Maybe a movie too.  There are close to a hundred patches that need to be downloaded and applied.  Avoiding that mess was why I put so much time into trying to get the 2008 R2 version working.  Maybe next time.  Don’t forget to add the extensions for VMLite (or whatever virtualization product you prefer). Set a fixed IP address on the internal-only NIC.  Do not give it a gateway.  Put the same IP address for the NIC and for the DNS Server.  This IP should be in a range that is never available on your public network.  You will need all the addresses in the range available.  See the previous post for the exact settings I used. I chose 10.97.230.1 as the server.  The rest of the 10.97.230 range is what I will use later.  For the curious, those numbers are based on elements of my home address.  Not truly random, but good enough for this project. Do not bridge the network connections.  I never allowed the cluster nodes direct access to any public network. Format the fixed VHD and leave it alone for now. Promote the VM to a Domain Controller.  If you have never done this, don’t worry.  The only meaningful decision is what to call the new domain.  I prefer a bogus name that does not correspond to a real Top-Level Domain (TLD).  .com, .biz., .net, .org  are all TLDs that we know and love.  I chose .test as the TLD since it is descriptive AND it does not exist in the real world.  The domain is called MicroAD.  This gives me MicroAD.Test as my domain. During the promotion process, you will be prompted to install DNS as part of the Domain creation process.  You want to accept this option.  The installer will automatically assign this DNS server as the authoritative owner of the MicroAD.test DNS domain (not to be confused with the MicroAD.test Active Directory domain.) For the rest of the DCPROMO process, just accept the defaults. Now let’s make our IP address management easy.  Add the DHCP Role to the server.  Add the server (10.97.230.1 in this case) as the default gateway to assign to DHCP clients.  Here is where you have to be VERY careful and bind it ONLY to the Internal NIC.  Trust me, your network admin will NOT like an extra DHCP server “helping” out on her network.  Go ahead and create a range of 10-20 IP Addresses in your scope.  You might find other uses for a pocket domain controller <cough> Mirroring </cough> than just for building a cluster.  And Clustering in SQL 2008 and Windows 2008 R2 fully supports DHCP addresses. Now we have three of the five key roles ready.  Two more to go. Next comes file sharing.  Since your cluster node VMs will not have access to any outside, you have to have some way to get files into these VMs.  I simply go to the root of C: and create a “Shared” folder.  I then share it out and grant full control to “Everyone” to both the share and to the underlying NTFS folder.   This will be immensely useful for Service Packs, demo databases, and any other software that isn’t packaged as an ISO that we can mount to the VM. Finally we need to create a block-level multi-connect storage device.  The kind folks at Starwinds Software (http://www.starwindsoftware.com/) graciously gave me a non-expiring demo license for expressly this purpose.  Their iSCSI SAN software lets you create an iSCSI target from nearly any storage medium.  Refreshingly, their product does exactly what they say it does.  Thanks. Remember that 16 GB VHD file?  That is where we are going to carve into our LUNs.  I created an iSCSI folder off the root, just so I can keep everything organized.  I then carved 5 ea. 2 GB iSCSI targets from that folder.  I chose a fixed VHD for performance.  I tried this earlier with a dynamically expanding VHD, but too many layers of abstraction and sparseness combined to make it unusable even for a demo.  Stick with a fixed VHD so there is a one-to-one mapping between abstract and physical storage.  If you read the previous post, you know what I named these iSCSI LUNs and why.  Yes, I do have some left over space.  Always leave yourself room for future growth or options. This gets us up to where we can actually build the nodes and install SQL.  As with most clusters, the real work happens long before the individual nodes get installed and configured.  At least it does if you want the cluster to be a true high-availability platform.

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• You Say You Want a (Customer Experience) Revolution

  - by Christie Flanagan

  Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} rev-o-lu-tion [rev-uh-loo-shuhn] noun 1. a sudden, radical or complete change 2. fundamental change in the way of thinking about or visualizing something; a change of paradigm 3. a changeover in use or preference especially in technology <the computer revolution> Lately, I've been hearing an awful lot about the customer experience revolution.  Tonight Oracle will be hosting The Experience Revolution, an evening of exploration and networking with customer experience executives in New York City where Oracle President Mark Hurd will introduce Oracle Customer Experience, a cross-stack suite of customer experience products that includes Oracle WebCenter and a number of other Oracle technologies. Then on Tuesday and Wednesday, the Forrester Customer Experience Forum East also kicks off in New York City where they'll examine how businesses can "reap the full business benefits of the customer experience revolution." So, are we in the midst of a customer experience revolution? As a consumer, I can answer that question with a definitive “yes.” When I bought my very first car, I had a lot of questions. How do I know if I’m paying a fair price? How do I know if this dealer is honest? Why do I have to sit through these good cop, bad cop shenanigans between sales and sales management at the dealership? Why do I feel like I’m doing these people a favor by giving them my business? In the end the whole experience left me feeling deeply unsatisfied. I didn’t feel that I held all that much power over the experience and the only real negotiating trick I had was to walk out, which I did, many times before actually making a purchase. Fast forward to a year ago and I found myself back in the market for a new car. The very first car that I bought had finally kicked the bucket after many years, many repair bills, and much wear and tear. Man, I had loved that car. It was time to move on, but I had a knot in my stomach when I reflected back on my last car purchase experience and dreaded the thought of going through that again. Could that have been the reason why I drove my old car for so long? But as I started the process of researching new cars, I started to feel really confident. I had a wealth of online information that helped me in my search. I went to Edmunds and plugged in some information on my preferences and left with a short list of vehicles. After an afternoon spent test driving the cars my short list, I had determined my favorite – it was a model I didn’t even know about until my research on Edmunds! But I didn’t want to go back to the dealership where I test drove it. They were clearly old school and wanted me to buy the way that they wanted to sell. No thanks! After that I went back online. I figured out exactly what people had paid for this car in my area. I found out what kind of discount others were able to negotiate from an online community forum dedicated to the make and model. I found out how the sales people were being incentivized by the manufacturer that month. I learned which dealers had the best ratings and reviews. This was actually getting exciting. I was feeling really empowered. My next step was to request online quotes from the some of the highest rated dealers but I already knew exactly how much I was going to pay. This was really a test for the dealers. My new mantra was “let he who delivers the best customer experience win.” An inside sales rep from one dealer responded to my quote request within a couple of hours. I told him I had already decided on the make and model and it was just a matter of figuring out who I would buy it from. I also told them that I was really busy and wouldn’t set foot in the dealership unless we had come to terms beforehand. Lastly, I let him know that I’d prefer to work out the details via email. He promised to get back to me shortly with a detailed quote. Over the next few days I received calls from other dealers. One asked me a host of questions that I had already answered in their lengthy online form. Another blamed their website performance issues for their delay in responding to my request. But by then it didn’t really matter because I’d already bought the car days before from the dealer who responded to me first and who was willing to adjust their sales process to accommodate my buying one. So, yes, I really do believe we are in the midst of a customer experience revolution. And every revolution leaves some victorious and other vanquished. Which side do you want to be on when it comes to the customer experience revolution?

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• SSAO Distortion

  - by Robert Xu

  I'm currently (attempting) to add SSAO to my engine, except it's...not really work, to say the least. I use a deferred renderer to render my scene. I have four render targets: Albedo, Light, Normal, and Depth. Here are the parameters for all of them (Surface Format, Depth Format): Albedo: 32-bit ARGB, Depth24Stencil8 Light: 32-bit ARGB, None Normal: 32-bit ARGB, None Depth: 8-bit R (Single), Depth24Stencil8 To generate my random noise map for the SSAO, I do the following for each pixel in the noise map: Vector3 v3 = Vector3.Zero; double z = rand.NextDouble() * 2.0 - 1.0; double r = Math.Sqrt(1.0 - z * z); double angle = rand.NextDouble() * MathHelper.TwoPi; v3.X = (float)(r * Math.Cos(angle)); v3.Y = (float)(r * Math.Sin(angle)); v3.Z = (float)z; v3 += offset; v3 *= 0.5f; result[i] = new Color(v3); This is my GBuffer rendering effect: PixelInput RenderGBufferColorVertexShader(VertexInput input) { PixelInput pi = ( PixelInput ) 0; pi.Position = mul(input.Position, WorldViewProjection); pi.Normal = mul(input.Normal, WorldInverseTranspose); pi.Color = input.Color; pi.TPosition = pi.Position; pi.WPosition = input.Position; return pi; } GBufferTarget RenderGBufferColorPixelShader(PixelInput input) { GBufferTarget output = ( GBufferTarget ) 0; float3 position = input.TPosition.xyz / input.TPosition.w; output.Albedo = lerp(float4(1.0f, 1.0f, 1.0f, 1.0f), input.Color, ColorFactor); output.Normal = EncodeNormal(input.Normal); output.Depth = position.z; return output; } And here is the SSAO effect: float4 EncodeNormal(float3 normal) { return float4((normal.xyz * 0.5f) + 0.5f, 0.0f); } float3 DecodeNormal(float4 encoded) { return encoded * 2.0 - 1.0f; } float Intensity; float Size; float2 NoiseOffset; float4x4 ViewProjection; float4x4 ViewProjectionInverse; texture DepthMap; texture NormalMap; texture RandomMap; const float3 samples[16] = { float3(0.01537562, 0.01389096, 0.02276565), float3(-0.0332658, -0.2151698, -0.0660736), float3(-0.06420016, -0.1919067, 0.5329634), float3(-0.05896204, -0.04509097, -0.03611697), float3(-0.1302175, 0.01034653, 0.01543675), float3(0.3168565, -0.182557, -0.01421785), float3(-0.02134448, -0.1056605, 0.00576055), float3(-0.3502164, 0.281433, -0.2245609), float3(-0.00123525, 0.00151868, 0.02614773), float3(0.1814744, 0.05798516, -0.02362876), float3(0.07945167, -0.08302628, 0.4423518), float3(0.321987, -0.05670302, -0.05418307), float3(-0.00165138, -0.00410309, 0.00537362), float3(0.01687791, 0.03189049, -0.04060405), float3(-0.04335613, -0.00530749, 0.06443053), float3(0.8474263, -0.3590308, -0.02318038), }; sampler DepthSampler = sampler_state { Texture = DepthMap; MipFilter = Point; MinFilter = Point; MagFilter = Point; AddressU = Clamp; AddressV = Clamp; AddressW = Clamp; }; sampler NormalSampler = sampler_state { Texture = NormalMap; MipFilter = Linear; MinFilter = Linear; MagFilter = Linear; AddressU = Clamp; AddressV = Clamp; AddressW = Clamp; }; sampler RandomSampler = sampler_state { Texture = RandomMap; MipFilter = Linear; MinFilter = Linear; MagFilter = Linear; }; struct VertexInput { float4 Position : POSITION0; float2 TextureCoordinates : TEXCOORD0; }; struct PixelInput { float4 Position : POSITION0; float2 TextureCoordinates : TEXCOORD0; }; PixelInput SSAOVertexShader(VertexInput input) { PixelInput pi = ( PixelInput ) 0; pi.Position = input.Position; pi.TextureCoordinates = input.TextureCoordinates; return pi; } float3 GetXYZ(float2 uv) { float depth = tex2D(DepthSampler, uv); float2 xy = uv * 2.0f - 1.0f; xy.y *= -1; float4 p = float4(xy, depth, 1); float4 q = mul(p, ViewProjectionInverse); return q.xyz / q.w; } float3 GetNormal(float2 uv) { return DecodeNormal(tex2D(NormalSampler, uv)); } float4 SSAOPixelShader(PixelInput input) : COLOR0 { float depth = tex2D(DepthSampler, input.TextureCoordinates); float3 position = GetXYZ(input.TextureCoordinates); float3 normal = GetNormal(input.TextureCoordinates); float occlusion = 1.0f; float3 reflectionRay = DecodeNormal(tex2D(RandomSampler, input.TextureCoordinates + NoiseOffset)); for (int i = 0; i < 16; i++) { float3 sampleXYZ = position + reflect(samples[i], reflectionRay) * Size; float4 screenXYZW = mul(float4(sampleXYZ, 1.0f), ViewProjection); float3 screenXYZ = screenXYZW.xyz / screenXYZW.w; float2 sampleUV = float2(screenXYZ.x * 0.5f + 0.5f, 1.0f - (screenXYZ.y * 0.5f + 0.5f)); float frontMostDepthAtSample = tex2D(DepthSampler, sampleUV); if (frontMostDepthAtSample < screenXYZ.z) { occlusion -= 1.0f / 16.0f; } } return float4(occlusion * Intensity * float3(1.0, 1.0, 1.0), 1.0); } technique SSAO { pass Pass0 { VertexShader = compile vs_3_0 SSAOVertexShader(); PixelShader = compile ps_3_0 SSAOPixelShader(); } } However, when I use the effect, I get some pretty bad distortion: Here's the light map that goes with it -- is the static-like effect supposed to be like that? I've noticed that even if I'm looking at nothing, I still get the static-like effect. (you can see it in the screenshot; the top half doesn't have any geometry yet it still has the static-like effect) Also, does anyone have any advice on how to effectively debug shaders?

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• Why Is Faulty Behaviour In The .NET Framework Not Fixed?

  - by Alois Kraus

  Here is the scenario: You have a Windows Form Application that calls a method via Invoke or BeginInvoke which throws exceptions. Now you want to find out where the error did occur and how the method has been called. Here is the output we do get when we call Begin/EndInvoke or simply Invoke The actual code that was executed was like this:         private void cInvoke_Click(object sender, EventArgs e)         {             InvokingFunction(CallMode.Invoke);         }            [MethodImpl(MethodImplOptions.NoInlining)]         void InvokingFunction(CallMode mode)         {             switch (mode)             {                 case CallMode.Invoke:                     this.Invoke(new MethodInvoker(GenerateError));   The faulting method is called GenerateError which does throw a NotImplementedException exception and wraps it in a NotSupportedException.           [MethodImpl(MethodImplOptions.NoInlining)]         void GenerateError()         {             F1();         }           private void F1()         {             try             {                 F2();             }             catch (Exception ex)             {                 throw new NotSupportedException("Outer Exception", ex);             }         }           private void F2()         {            throw new NotImplementedException("Inner Exception");         } It is clear that the method F2 and F1 did actually throw these exceptions but we do not see them in the call stack. If we directly call the InvokingFunction and catch and print the exception we can find out very easily how we did get into this situation. We see methods F1,F2,GenerateError and InvokingFunction directly in the stack trace and we see that actually two exceptions did occur. Here is for comparison what we get from Invoke/EndInvoke System.NotImplementedException: Inner Exception     StackTrace:    at System.Windows.Forms.Control.MarshaledInvoke(Control caller, Delegate method, Object[] args, Boolean synchronous)     at System.Windows.Forms.Control.Invoke(Delegate method, Object[] args)     at WindowsFormsApplication1.AppForm.InvokingFunction(CallMode mode)     at WindowsFormsApplication1.AppForm.cInvoke_Click(Object sender, EventArgs e)     at System.Windows.Forms.Control.OnClick(EventArgs e)     at System.Windows.Forms.Button.OnClick(EventArgs e) The exception message is kept but the stack starts running from our Invoke call and not from the faulting method F2. We have therefore no clue where this exception did occur! The stack starts running at the method MarshaledInvoke because the exception is rethrown with the throw catchedException which resets the stack trace. That is bad but things are even worse because if previously lets say 5 exceptions did occur .NET will return only the first (innermost) exception. That does mean that we do not only loose the original call stack but all other exceptions and all data contained therein as well. It is a pity that MS does know about this and simply closes this issue as not important. Programmers will play a lot more around with threads than before thanks to TPL, PLINQ that do come with .NET 4. Multithreading is hyped quit a lot in the press and everybody wants to use threads. But if the .NET Framework makes it nearly impossible to track down the easiest UI multithreading issue I have a problem with that. The problem has been reported but obviously not been solved. .NET 4 Beta 2 did not have changed that dreaded GetBaseException call in MarshaledInvoke to return only the innermost exception of the complete exception stack. It is really time to fix this. WPF on the other hand does the right thing and wraps the exceptions inside a TargetInvocationException which makes much more sense. But Not everybody uses WPF for its daily work and Windows forms applications will still be used for a long time. Below is the code to repro the issues shown and how the exceptions can be rendered in a meaningful way. The default Exception.ToString implementation generates a hard to interpret stack if several nested exceptions did occur. using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; using System.Threading; using System.Globalization; using System.Runtime.CompilerServices;   namespace WindowsFormsApplication1 {     public partial class AppForm : Form     {         enum CallMode         {             Direct = 0,             BeginInvoke = 1,             Invoke = 2         };           public AppForm()         {             InitializeComponent();             Thread.CurrentThread.CurrentUICulture = CultureInfo.InvariantCulture;             Application.ThreadException += new System.Threading.ThreadExceptionEventHandler(Application_ThreadException);         }           void Application_ThreadException(object sender, System.Threading.ThreadExceptionEventArgs e)         {             cOutput.Text = PrintException(e.Exception, 0, null).ToString();         }           private void cDirectUnhandled_Click(object sender, EventArgs e)         {             InvokingFunction(CallMode.Direct);         }           private void cDirectCall_Click(object sender, EventArgs e)         {             try             {                 InvokingFunction(CallMode.Direct);             }             catch (Exception ex)             {                 cOutput.Text = PrintException(ex, 0, null).ToString();             }         }           private void cInvoke_Click(object sender, EventArgs e)         {             InvokingFunction(CallMode.Invoke);         }           private void cBeginInvokeCall_Click(object sender, EventArgs e)         {             InvokingFunction(CallMode.BeginInvoke);         }           [MethodImpl(MethodImplOptions.NoInlining)]         void InvokingFunction(CallMode mode)         {             switch (mode)             {                 case CallMode.Direct:                     GenerateError();                     break;                 case CallMode.Invoke:                     this.Invoke(new MethodInvoker(GenerateError));                     break;                 case CallMode.BeginInvoke:                     IAsyncResult res = this.BeginInvoke(new MethodInvoker(GenerateError));                     this.EndInvoke(res);                     break;             }         }           [MethodImpl(MethodImplOptions.NoInlining)]         void GenerateError()         {             F1();         }           private void F1()         {             try             {                 F2();             }             catch (Exception ex)             {                 throw new NotSupportedException("Outer Exception", ex);             }         }           private void F2()         {            throw new NotImplementedException("Inner Exception");         }           StringBuilder PrintException(Exception ex, int identLevel, StringBuilder sb)         {             StringBuilder builtStr = sb;             if( builtStr == null )                 builtStr = new StringBuilder();               if( ex == null )                 return builtStr;                 WriteLine(builtStr, String.Format("{0}: {1}", ex.GetType().FullName, ex.Message), identLevel);             WriteLine(builtStr, String.Format("StackTrace: {0}", ShortenStack(ex.StackTrace)), identLevel + 1);             builtStr.AppendLine();               return PrintException(ex.InnerException, ++identLevel, builtStr);         }               void WriteLine(StringBuilder sb, string msg, int identLevel)         {             foreach (string trimmedLine in SplitToLines(msg)                                            .Select( (line) => line.Trim()) )             {                 for (int i = 0; i < identLevel; i++)                     sb.Append('\t');                 sb.Append(trimmedLine);                 sb.AppendLine();             }         }           string ShortenStack(string stack)         {             int nonAppFrames = 0;             // Skip stack frames not part of our app but include two foreign frames and skip the rest             // If our stack frame is encountered reset counter to 0             return SplitToLines(stack)                               .Where((line) =>                               {                                   nonAppFrames = line.Contains("WindowsFormsApplication1") ? 0 : nonAppFrames + 1;                                   return nonAppFrames < 3;                               })                              .Select((line) => line)                              .Aggregate("", (current, line) => current + line + Environment.NewLine);         }           static char[] NewLines = Environment.NewLine.ToCharArray();         string[] SplitToLines(string str)         {             return str.Split(NewLines, StringSplitOptions.RemoveEmptyEntries);         }     } }

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• SortedDictionary and SortedList

  - by Simon Cooper

  Apart from Dictionary<TKey, TValue>, there's two other dictionaries in the BCL - SortedDictionary<TKey, TValue> and SortedList<TKey, TValue>. On the face of it, these two classes do the same thing - provide an IDictionary<TKey, TValue> interface where the iterator returns the items sorted by the key. So what's the difference between them, and when should you use one rather than the other? (as in my previous post, I'll assume you have some basic algorithm & datastructure knowledge) SortedDictionary We'll first cover SortedDictionary. This is implemented as a special sort of binary tree called a red-black tree. Essentially, it's a binary tree that uses various constraints on how the nodes of the tree can be arranged to ensure the tree is always roughly balanced (for more gory algorithmical details, see the wikipedia link above). What I'm concerned about in this post is how the .NET SortedDictionary is actually implemented. In .NET 4, behind the scenes, the actual implementation of the tree is delegated to a SortedSet<KeyValuePair<TKey, TValue>>. One example tree might look like this: Each node in the above tree is stored as a separate SortedSet<T>.Node object (remember, in a SortedDictionary, T is instantiated to KeyValuePair<TKey, TValue>): class Node { public bool IsRed; public T Item; public SortedSet<T>.Node Left; public SortedSet<T>.Node Right; } The SortedSet only stores a reference to the root node; all the data in the tree is accessed by traversing the Left and Right node references until you reach the node you're looking for. Each individual node can be physically stored anywhere in memory; what's important is the relationship between the nodes. This is also why there is no constructor to SortedDictionary or SortedSet that takes an integer representing the capacity; there are no internal arrays that need to be created and resized. This may seen trivial, but it's an important distinction between SortedDictionary and SortedList that I'll cover later on. And that's pretty much it; it's a standard red-black tree. Plenty of webpages and datastructure books cover the algorithms behind the tree itself far better than I could. What's interesting is the comparions between SortedDictionary and SortedList, which I'll cover at the end. As a side point, SortedDictionary has existed in the BCL ever since .NET 2. That means that, all through .NET 2, 3, and 3.5, there has been a bona-fide sorted set class in the BCL (called TreeSet). However, it was internal, so it couldn't be used outside System.dll. Only in .NET 4 was this class exposed as SortedSet. SortedList Whereas SortedDictionary didn't use any backing arrays, SortedList does. It is implemented just as the name suggests; two arrays, one containing the keys, and one the values (I've just used random letters for the values): The items in the keys array are always guarenteed to be stored in sorted order, and the value corresponding to each key is stored in the same index as the key in the values array. In this example, the value for key item 5 is 'z', and for key item 8 is 'm'. Whenever an item is inserted or removed from the SortedList, a binary search is run on the keys array to find the correct index, then all the items in the arrays are shifted to accomodate the new or removed item. For example, if the key 3 was removed, a binary search would be run to find the array index the item was at, then everything above that index would be moved down by one: and then if the key/value pair {7, 'f'} was added, a binary search would be run on the keys to find the index to insert the new item, and everything above that index would be moved up to accomodate the new item: If another item was then added, both arrays would be resized (to a length of 10) before the new item was added to the arrays. As you can see, any insertions or removals in the middle of the list require a proportion of the array contents to be moved; an O(n) operation. However, if the insertion or removal is at the end of the array (ie the largest key), then it's only O(log n); the cost of the binary search to determine it does actually need to be added to the end (excluding the occasional O(n) cost of resizing the arrays to fit more items). As a side effect of using backing arrays, SortedList offers IList Keys and Values views that simply use the backing keys or values arrays, as well as various methods utilising the array index of stored items, which SortedDictionary does not (and cannot) offer. The Comparison So, when should you use one and not the other? Well, here's the important differences: Memory usage SortedDictionary and SortedList have got very different memory profiles. SortedDictionary... has a memory overhead of one object instance, a bool, and two references per item. On 64-bit systems, this adds up to ~40 bytes, not including the stored item and the reference to it from the Node object. stores the items in separate objects that can be spread all over the heap. This helps to keep memory fragmentation low, as the individual node objects can be allocated wherever there's a spare 60 bytes. In contrast, SortedList... has no additional overhead per item (only the reference to it in the array entries), however the backing arrays can be significantly larger than you need; every time the arrays are resized they double in size. That means that if you add 513 items to a SortedList, the backing arrays will each have a length of 1024. To conteract this, the TrimExcess method resizes the arrays back down to the actual size needed, or you can simply assign list.Capacity = list.Count. stores its items in a continuous block in memory. If the list stores thousands of items, this can cause significant problems with Large Object Heap memory fragmentation as the array resizes, which SortedDictionary doesn't have. Performance Operations on a SortedDictionary always have O(log n) performance, regardless of where in the collection you're adding or removing items. In contrast, SortedList has O(n) performance when you're altering the middle of the collection. If you're adding or removing from the end (ie the largest item), then performance is O(log n), same as SortedDictionary (in practice, it will likely be slightly faster, due to the array items all being in the same area in memory, also called locality of reference). So, when should you use one and not the other? As always with these sort of things, there are no hard-and-fast rules. But generally, if you: need to access items using their index within the collection are populating the dictionary all at once from sorted data aren't adding or removing keys once it's populated then use a SortedList. But if you: don't know how many items are going to be in the dictionary are populating the dictionary from random, unsorted data are adding & removing items randomly then use a SortedDictionary. The default (again, there's no definite rules on these sort of things!) should be to use SortedDictionary, unless there's a good reason to use SortedList, due to the bad performance of SortedList when altering the middle of the collection.

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• class hierarchy design for small java project

  - by user523956

  I have written a java code which does following:- Main goal is to fetch emails from (inbox, spam) folders and store them in database. It fetches emails from gmail,gmx,web.de,yahoo and Hotmail. Following attributes are stored in mysql database. Slno, messagedigest, messageid, foldername, dateandtime, receiver, sender, subject, cc, size and emlfile. For gmail,gmy and web.de, I have used javamail API, because email form it can be fetched with IMAP. For yahoo and hotmail, I have used html parser and httpclient to fetch emails form spam folder and for inbox folder, I have used pop3 javamail API. I want to have proper class hierarchy which makes my code efficient and easily reusable. As of now I have designed class hierarchy as below: I am sure it can still be improved. So I would like to have different opinions on it. I have following classes and methods as of now. MainController:- Here I pass emailid, password and foldername from which emails have to be fetched. Abstract Class :-EmailProtocol Abstract Methods of it (All methods except executeParser contains method definition):- connectImap() // used by gmx,gmail and web.de email ids connectPop3() // used by hotmail and yahoo to fetch emails of inbox folder createMessageDigest // used by every email provider(gmx, gmail,web.de,yahoo,hotmail) establishDBConnection // used by every email emailAlreadyExists // used by every email which checks whether email already exists in db or not, if not then store it. storeemailproperties // used by every email to store emails properties to mysql database executeParser // nothing written in it. Overwridden and used by just hotmail and yahoo to fetch emails form spam folder. Imap extends EmailProtocol (nothing in it. But I have to have it to access methods of EmailProtocol. This is used to fetch emails from gmail,gmx and web.de) I know this is really a bad way but don't know how to do it other way. Hotmsil extends EmailProtocol Methods:- executeParser() :- This is used by just hotmail email id. fetchjunkemails() :- This is also very specific for only hotmail email id. Yahoo extends EmailProtocol Methods:- executeParser() storeEmailtotemptable() MoveEmailtoInbox() getFoldername() nullorEquals() All above methods are specific for yahoo email id. public DateTimeFormat(class) format() //this formats datetime of gmax,gmail and web.de emails. formatYahoodate //this formats datetime of yahoo email. formatHotmaildate // this formats datetime of hotmail email. public StringFormat ConvertStreamToString() // Accessed by every class except DateTimeFormat class. formatFromTo() // Accessed by every class except DateTimeFormat class. public Class CheckDatabaseExistance public static void checkForDatabaseTablesAvailability() (This method checks at the beginnning whether database and required tables exist in mysql or not. if not it creates them) Please see code of my MainController class so that You can have an idea about how I use different classes. public class MainController { public static void main(String[] args) throws Exception { ArrayList<String> web_de_folders = new ArrayList<String>(); web_de_folders.add("INBOX"); web_de_folders.add("Unbekannt"); web_de_folders.add("Spam"); web_de_folders.add("OUTBOX"); web_de_folders.add("SENT"); web_de_folders.add("DRAFTS"); web_de_folders.add("TRASH"); web_de_folders.add("Trash"); ArrayList<String> gmx_folders = new ArrayList<String>(); gmx_folders.add("INBOX"); gmx_folders.add("Archiv"); gmx_folders.add("Entwürfe"); gmx_folders.add("Gelöscht"); gmx_folders.add("Gesendet"); gmx_folders.add("Spamverdacht"); gmx_folders.add("Trash"); ArrayList<String> gmail_folders = new ArrayList<String>(); gmail_folders.add("Inbox"); gmail_folders.add("[Google Mail]/Spam"); gmail_folders.add("[Google Mail]/Trash"); gmail_folders.add("[Google Mail]/Sent Mail"); ArrayList<String> pop3_folders = new ArrayList<String>(); pop3_folders.add("INBOX"); CheckDatabaseExistance.checkForDatabaseTablesAvailability(); EmailProtocol imap = new Imap(); System.out.println("CHECKING FOR NEW EMAILS IN WEB.DE...(IMAP)"); System.out.println("*********************************************************************************"); imap.connectImap("[email protected]", "pwd", web_de_folders); System.out.println("\nCHECKING FOR NEW EMAILS IN GMX.DE...(IMAP)"); System.out.println("*********************************************************************************"); imap.connectImap("[email protected]", "pwd", gmx_folders); System.out.println("\nCHECKING FOR NEW EMAILS IN GMAIL...(IMAP)"); System.out.println("*********************************************************************************"); imap.connectImap("[email protected]", "pwd", gmail_folders); EmailProtocol yahoo = new Yahoo(); Yahoo y=new Yahoo(); System.out.println("\nEXECUTING YAHOO PARSER"); System.out.println("*********************************************************************************"); y.executeParser("http://de.mc1321.mail.yahoo.com/mc/welcome?ymv=0","[email protected]","pwd"); System.out.println("\nCHECKING FOR NEW EMAILS IN INBOX OF YAHOO (POP3)"); System.out.println("*********************************************************************************"); yahoo.connectPop3("[email protected]","pwd",pop3_folders); System.out.println("\nCHECKING FOR NEW EMAILS IN INBOX OF HOTMAIL (POP3)"); System.out.println("*********************************************************************************"); yahoo.connectPop3("[email protected]","pwd",pop3_folders); EmailProtocol hotmail = new Hotmail(); Hotmail h=new Hotmail(); System.out.println("\nEXECUTING HOTMAIL PARSER"); System.out.println("*********************************************************************************"); h.executeParser("https://login.live.com/ppsecure/post.srf","[email protected]","pwd"); } } I have kept DatetimeFormat and StringFormat class public so that I can access its public methods by just (DatetimeFormat.formatYahoodate for e.g. from different methods). This is the first time I have developed something in java. It serves its purpose but of course code is still not so efficient I think. I need your suggestions on this project.

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• NVIDIA x server - "sudo nvidia config" does not generate a working 'xorg.config'

  - by Mike

  I am over 18 hours deep on this challenge. I got to this point and am stuck. very stuck. Maybe you can figure it out? Ubuntu Version 12.04 LTS with all the updates installed. Problem: The default settings in "etc/X11/xorg.conf" that are generated by the "nvidia-xconfig" tool, do not allow the NVIDIA x server to connect to the driver in my "System Settings Additional Driver window". (that's how I understand it. Lots of information below). Symptoms of Problem "System Settings Additional Driver" window has drivers, but the nvidia x server cannot connect/utilize any of the 4 drivers. the drivers are activated, but not in use. When I go to "System Tools Administration NVIDIA x server settings" I get an error that basically tells me to create a default file to initialize the NVIDIA X server (screen shot below). This is the messages the terminal gives after running a "sudo nvidia-xconfig" command for the first time. It seems that the generated file by the tool i just ran is generating a bad/unusable file: If I run the "sudo nvidia-xconfig" command again, I wont get an error the second time. However when I reboot, the default file that is generated (etc/X11/xorg.conf) simply puts the screen resolution at 800 x 600 (or something big like that). When I try to go to NVIDIA x server settings I am greeted with the same screen as the screen shot as in symptom 2 (no option to change the resolution). If I try to go to "system settings display" there are no other resolutions to choose from. At this point I must delete the newly minted "xorg.conf" and reinstate the original in its place. Here are the contents of the "xorg.conf" that is generated first (the one missing required information): # nvidia-xconfig: X configuration file generated by nvidia-xconfig # nvidia-xconfig: version 304.88 (buildmeister@swio-display-x86-rhel47-06) Wed Mar 27 15:32:58 PDT 2013 Section "ServerLayout" Identifier "Layout0" Screen 0 "Screen0" InputDevice "Keyboard0" "CoreKeyboard" InputDevice "Mouse0" "CorePointer" EndSection Section "Files" EndSection Section "InputDevice" # generated from default Identifier "Mouse0" Driver "mouse" Option "Protocol" "auto" Option "Device" "/dev/psaux" Option "Emulate3Buttons" "no" Option "ZAxisMapping" "4 5" EndSection Section "InputDevice" # generated from default Identifier "Keyboard0" Driver "kbd" EndSection Section "Monitor" Identifier "Monitor0" VendorName "Unknown" ModelName "Unknown" HorizSync 28.0 - 33.0 VertRefresh 43.0 - 72.0 Option "DPMS" EndSection Section "Device" Identifier "Device0" Driver "nvidia" VendorName "NVIDIA Corporation" EndSection Section "Screen" Identifier "Screen0" Device "Device0" Monitor "Monitor0" DefaultDepth 24 SubSection "Display" Depth 24 EndSubSection EndSection Hardware: I ran the "lspci|grep VGA". There results are: 00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09) 01:00.0 VGA compatible controller: NVIDIA Corporation GF108 [Quadro 1000M] (rev a1) More Hardware info: Ram: 16GB CPU: Intel Core i7-2720QM @2.2GHz * 8 Other: 64 bit. This is a triple boot computer and not a VM. Attempts With Not Success on My End: 1) Tried to append the "xorg.conf" with what I perceive is missing information and obviously it didn't fly. 2) All the other stuff I tried got me to this point. 3) See if this link is helpful to you (I barely get it, but i get enough knowing that a smarter person might find this useful): http://manpages.ubuntu.com/manpages/lucid/man1/nvidia-xconfig.1.html 4) I am completely new to Linux (40 hours over past week), but not to programming. However I am very serious about changing over to Linux. When you respond (I hope someone responds...) please respond in a way that a person new to Linux can understand. 5) By the way, the reason I am in this mess is because I MUST have a second monitor running from my laptop, and "System Settings Display" doesn't recognize my second display. I know it is possible to make the second display work in my system, because when I boot from the install CD, I perform work on the native laptop monitor, but the second monitor shows a purple screen with Ubuntu in the middle, so I know the VGA port is sending a signal out. If this is too much for you to tackle please suggest an alternative method to get a second display. I don't want to go to windows but I cannot have a single display. I am really fudged here. I hope some smart person can help. Thanks in advance. Mike. **********************EDIT #1********************** More Details About Graphics Card I was asked "which brand of nvidia-card do you have exactly?" Here is what I did to provide more info (maybe relevant, maybe not, but here is everything): 1) Took my Lenovo W520 right apart to see if there is an identifier on the actual card. However I realized that if I get deep enough to take a look, the laptop "won't like it". so I put it back together. Figuring out the card this way is not an option for me right now. 2) (My computer is triple boot) I logged into Win7 and ran 'dxdiag' command. here is the screen shot: 3) I tried to look on the lenovo website for more details... but no luck. I took a look at my receipts and here is info form receipt: System Unit: W520 NVIDIA Quadro 1000M 2GB 4) In win7 I went to the NVIDIA website and used the option to have my card 'scanned' by a Java applet to determine the latest update for my card. I tried the same with Ubuntu but I can't get the applet to run. Here is the recommended driver from from the NVIDIA Applet for my card for Win7 (I hope this shines some light on the specifics of the card): Quadro/NVS/Tesla/GRID Desktop Driver Release R319 Version: 320.00 WHQL Release Date: 3.5.2013 5) Also I went on the NVIDIA driver search and looked through every possible combination of product type + product series + product to find all the combinations that yield a 1000M card. My card is: Product Type: Quadro Product Series: Quadro Series (Notebooks) Product: 1000M ***********************EDIT #2******************* Additional Symptoms Another question that generated more symptoms I previously didn't mention was: "After generating xorg.conf by nvidia-xconfig, go to additional drivers, do you see nvidia-304?" 1) I took a screen shot of the "additional drivers" right after generating xorg.conf by nvidia-xconfig. Here it is: 2) Then I did a reboot. Now Ubuntu is 600 x 800 resolution. When I logged in after the computer came up I got an error (which I always get after generating xorg.conf by nvidia-xconfig and rebooting) 3) To finally answer the question - No. There is no "NVIDIA-304" driver. Screen shot of additional drivers after generating xorg.conf by nvidia-xconfig and rebooting : At this point I revert to the original xorg.conf and delete the xorg.conf generated by Nvidia.

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• April Oracle Database Events

  - by Mandy Ho

  Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif";} April 17-18, 2012 – Moscow, Russia Oracle Develop Conference The Oracle database developer conference, Oracle Develop, will visit Moscow, Russia and Hyderabad, India this spring. Oracle Develop includes a database development track, which contains .NET sessions and hands-on lab led by an Oracle .NET product manager. Register today before the event fills up. http://www.oracle.com/javaone/ru-en/index.html Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif";} April 24, 26 – San Diego, CA & San Jose, CA ISC2 Leadership Regional Event Series Oracle at (ISC)2 Security Leadership Series: Herding Clouds -- Managing Cloud Security Concerns and Expectations Join us for his interactive day-long session where industry leaders, including Oracle solution experts, will talk about how to: dispel the top Cloud security myths minimize "rogue Cloud" implementations identify potential compliance pitfalls and how to avoid them develop contract language for your cloud providers manage users across your fractured datacenter leverage existing technologies to protect data as it moves from the enterprise to the cloud http://www.oracle.com/webapps/events/ns/EventsDetail.jsp?p_eventId=146972&src=7239493&src=7239493&Act=228 Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif";} April 22-26, 2012 – Las Vegas, NV IOUG Collaborate 12 From April 22-26, 2012, Oracle takes Las Vegas. Thousands of Oracle professionals will descend upon the Mandalay Bay Convention Center for a weeks worth of education sessions, networking opportunities and more, at the only user-driven and user-run Oracle conference - COLLABORATE 12.  Your COLLABORATE 12 - IOUG Forum registration comes complete with a bonus- a full day Deep Dive education program on Sunday! Choose from numerous hot topics, including Real World Performance, High Availability and more, presented by legendary and seasoned Oracle pros, including Tom Kyte and Craig Shallahamer. http://www.oracle.com/webapps/events/ns/EventsDetail.jsp?p_eventId=143637&src=7360364&src=7360364&Act=5 Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif";} Independent Oracle User Group (IOUG) Regional Events: April 16, 2012 – Columbus, Ohio Ohio Oracle Users Group Higher Performance PL/PQL and Oracle Database 11g PL/SQL New Features – Featuring Steven Feuerstein http://www.ooug.org/ Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif";} Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif";} April 26, 2012- Irving, TX Dallas Oracle Users Group Oracle Database Forum: 5-7PM Oracle Corporation, 6031 Connection Drive Irving, TX http://memberservices.membee.com/538/irmevents.aspx?id=64 Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif";} Apr 30, 2012- Los Angeles, CA Real World Performance Tour A full day of real world database performance with: Tom Kyte, author of the ever popular AskTom Blog, Andrew Holdsworth, head of Oracle's Real World Performance Team, and Graham Wood, renowned Oracle Database performance architect. Through discussion, debate and demos, they’ll show you how to master performance engineering topics like: Best practices for designing hardware architectures and how to spot and fix bad design. How to develop applications that deliver the fastest possible performance without sacrificing accuracy.  New for 2012! Updates on Enterprise Manager, Exadata, and what these technologies mean to your current systems. http://www.ioug.org/Events/ADayofRealWorldPerformance/tabid/194/Default.aspx

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• SQL SERVER – SSIS Look Up Component – Cache Mode – Notes from the Field #028

  - by Pinal Dave

  [Notes from Pinal]: Lots of people think that SSIS is all about arranging various operations together in one logical flow. Well, the understanding is absolutely correct, but the implementation of the same is not as easy as it seems. Similarly most of the people think lookup component is just component which does look up for additional information and does not pay much attention to it. Due to the same reason they do not pay attention to the same and eventually get very bad performance. Linchpin People are database coaches and wellness experts for a data driven world. In this 28th episode of the Notes from the Fields series database expert Tim Mitchell (partner at Linchpin People) shares very interesting conversation related to how to write a good lookup component with Cache Mode. In SQL Server Integration Services, the lookup component is one of the most frequently used tools for data validation and completion.  The lookup component is provided as a means to virtually join one set of data to another to validate and/or retrieve missing values.  Properly configured, it is reliable and reasonably fast. Among the many settings available on the lookup component, one of the most critical is the cache mode.  This selection will determine whether and how the distinct lookup values are cached during package execution.  It is critical to know how cache modes affect the result of the lookup and the performance of the package, as choosing the wrong setting can lead to poorly performing packages, and in some cases, incorrect results. Full Cache The full cache mode setting is the default cache mode selection in the SSIS lookup transformation.  Like the name implies, full cache mode will cause the lookup transformation to retrieve and store in SSIS cache the entire set of data from the specified lookup location.  As a result, the data flow in which the lookup transformation resides will not start processing any data buffers until all of the rows from the lookup query have been cached in SSIS. The most commonly used cache mode is the full cache setting, and for good reason.  The full cache setting has the most practical applications, and should be considered the go-to cache setting when dealing with an untested set of data. With a moderately sized set of reference data, a lookup transformation using full cache mode usually performs well.  Full cache mode does not require multiple round trips to the database, since the entire reference result set is cached prior to data flow execution. There are a few potential gotchas to be aware of when using full cache mode.  First, you can see some performance issues – memory pressure in particular – when using full cache mode against large sets of reference data.  If the table you use for the lookup is very large (either deep or wide, or perhaps both), there’s going to be a performance cost associated with retrieving and caching all of that data.  Also, keep in mind that when doing a lookup on character data, full cache mode will always do a case-sensitive (and in some cases, space-sensitive) string comparison even if your database is set to a case-insensitive collation.  This is because the in-memory lookup uses a .NET string comparison (which is case- and space-sensitive) as opposed to a database string comparison (which may be case sensitive, depending on collation).  There’s a relatively easy workaround in which you can use the UPPER() or LOWER() function in the pipeline data and the reference data to ensure that case differences do not impact the success of your lookup operation.  Again, neither of these present a reason to avoid full cache mode, but should be used to determine whether full cache mode should be used in a given situation. Full cache mode is ideally useful when one or all of the following conditions exist: The size of the reference data set is small to moderately sized The size of the pipeline data set (the data you are comparing to the lookup table) is large, is unknown at design time, or is unpredictable Each distinct key value(s) in the pipeline data set is expected to be found multiple times in that set of data Partial Cache When using the partial cache setting, lookup values will still be cached, but only as each distinct value is encountered in the data flow.  Initially, each distinct value will be retrieved individually from the specified source, and then cached.  To be clear, this is a row-by-row lookup for each distinct key value(s). This is a less frequently used cache setting because it addresses a narrower set of scenarios.  Because each distinct key value(s) combination requires a relational round trip to the lookup source, performance can be an issue, especially with a large pipeline data set to be compared to the lookup data set.  If you have, for example, a million records from your pipeline data source, you have the potential for doing a million lookup queries against your lookup data source (depending on the number of distinct values in the key column(s)).  Therefore, one has to be keenly aware of the expected row count and value distribution of the pipeline data to safely use partial cache mode. Using partial cache mode is ideally suited for the conditions below: The size of the data in the pipeline (more specifically, the number of distinct key column) is relatively small The size of the lookup data is too large to effectively store in cache The lookup source is well indexed to allow for fast retrieval of row-by-row values No Cache As you might guess, selecting no cache mode will not add any values to the lookup cache in SSIS.  As a result, every single row in the pipeline data set will require a query against the lookup source.  Since no data is cached, it is possible to save a small amount of overhead in SSIS memory in cases where key values are not reused.  In the real world, I don’t see a lot of use of the no cache setting, but I can imagine some edge cases where it might be useful. As such, it’s critical to know your data before choosing this option.  Obviously, performance will be an issue with anything other than small sets of data, as the no cache setting requires row-by-row processing of all of the data in the pipeline. I would recommend considering the no cache mode only when all of the below conditions are true: The reference data set is too large to reasonably be loaded into SSIS memory The pipeline data set is small and is not expected to grow There are expected to be very few or no duplicates of the key values(s) in the pipeline data set (i.e., there would be no benefit from caching these values) Conclusion The cache mode, an often-overlooked setting on the SSIS lookup component, represents an important design decision in your SSIS data flow.  Choosing the right lookup cache mode directly impacts the fidelity of your results and the performance of package execution.  Know how this selection impacts your ETL loads, and you’ll end up with more reliable, faster packages. If you want me to take a look at your server and its settings, or if your server is facing any issue we can Fix Your SQL Server. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: Notes from the Field, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL Tagged: SSIS

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• Grow Your Business with Security

  - by Darin Pendergraft

  Author: Kevin Moulton Kevin Moulton has been in the security space for more than 25 years, and with Oracle for 7 years. He manages the East EnterpriseSecurity Sales Consulting Team. He is also a Distinguished Toastmaster. Follow Kevin on Twitter at twitter.com/kevin_moulton, where he sometimes tweets about security, but might also tweet about running, beer, food, baseball, football, good books, or whatever else grabs his attention. Kevin will be a regular contributor to this blog so stay tuned for more posts from him. It happened again! There I was, reading something interesting online, and realizing that a friend might find it interesting too. I clicked on the little email link, thinking that I could easily forward this to my friend, but no! Instead, a new screen popped up where I was asked to create an account. I was expected to create a User ID and password, not to mention providing some personally identifiable information, just for the privilege of helping that website spread their word. Of course, I didn’t want to have to remember a new account and password, I didn’t want to provide the requisite information, and I didn’t want to waste my time. I gave up, closed the web page, and moved on to something else. I was left with a bad taste in my mouth, and my friend might never find her way to this interesting website. If you were this content provider, would this be the outcome you were looking for? A few days later, I had a similar experience, but this one went a little differently. I was surfing the web, when I happened upon some little chotcke that I just had to have. I added it to my cart. When I went to buy the item, I was again brought to a page to create account. Groan! But wait! On this page, I also had the option to sign in with my OpenID account, my Facebook account, my Yahoo account, or my Google Account. I have all of those! No new account to create, no new password to remember, and no personally identifiable information to be given to someone else (I’ve already given it all to those other guys, after all). In this case, the vendor was easy to deal with, and I happily completed the transaction. That pleasant experience will bring me back again. This is where security can grow your business. It’s a differentiator. You’ve got to have a presence on the web, and that presence has to take into account all the smart phones everyone’s carrying, and the tablets that took over cyber Monday this year. If you are a company that a customer can deal with securely, and do so easily, then you are a company customers will come back to again and again. I recently had a need to open a new bank account. Every bank has a web presence now, but they are certainly not all the same. I wanted one that I could deal with easily using my laptop, but I also wanted 2-factor authentication in case I had to login from a shared machine, and I wanted an app for my iPad. I found a bank with all three, and that’s who I am doing business with. Let’s say, for example, that I’m in a regular Texas Hold-em game on Friday nights, so I move a couple of hundred bucks from checking to savings on Friday afternoons. I move a similar amount each week and I do it from the same machine. The bank trusts me, and they trust my machine. Most importantly, they trust my behavior. This is adaptive authentication. There should be no reason for my bank to make this transaction difficult for me. Now let's say that I login from a Starbucks in Uzbekistan, and I transfer $2,500. What should my bank do now? Should they stop the transaction? Should they call my home number? (My former bank did exactly this once when I was taking money out of an ATM on a business trip, when I had provided my cell phone number as my primary contact. When I asked them why they called my home number rather than my cell, they told me that their “policy” is to call the home number. If I'm on the road, what exactly is the use of trying to reach me at home to verify my transaction?) But, back to Uzbekistan… Should my bank assume that I am happily at home in New Jersey, and someone is trying to hack into my account? Perhaps they think they are protecting me, but I wouldn’t be very happy if I happened to be traveling on business in Central Asia. What if my bank were to automatically analyze my behavior and calculate a risk score? Clearly, this scenario would be outside of my typical behavior, so my risk score would necessitate something more than a simple login and password. Perhaps, in this case, a one-time password to my cell phone would prove that this is not just some hacker half way around the world. But, what if you're not a bank? Do you need this level of security? If you want to be a business that is easy to deal with while also protecting your customers, then of course you do. You want your customers to trust you, but you also want them to enjoy doing business with you. Make it easy for them to do business with you, and they’ll come back, and perhaps even Tweet about it, or Like you, and then their friends will follow. How can Oracle help? Oracle has the technology and expertise to help you to grown your business with security. Oracle Adaptive Access Manager will help you to prevent fraud while making it easier for your customers to do business with you by providing the risk analysis I discussed above, step-up authentication, and much more. Oracle Mobile and Social Access Service will help you to secure mobile access to applications by expanding on your existing back-end identity management infrastructure, and allowing your customers to transact business with you using the social media accounts they already know. You also have device fingerprinting and metrics to help you to grow your business securely. Security is not just a cost anymore. It’s a way to set your business apart. With Oracle’s help, you can be the business that everyone’s tweeting about. Image courtesy of Flickr user shareski

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• SQL University: What and why of database testing

  - by Mladen Prajdic

  This is a post for a great idea called SQL University started by Jorge Segarra also famously known as SqlChicken on Twitter. It’s a collection of blog posts on different database related topics contributed by several smart people all over the world. So this week is mine and we’ll be talking about database testing and refactoring. In 3 posts we’ll cover: SQLU part 1 - What and why of database testing SQLU part 2 - What and why of database refactoring SQLU part 2 – Tools of the trade With that out of the way let us sharpen our pencils and get going. Why test a database The sad state of the industry today is that there is very little emphasis on testing in general. Test driven development is still a small niche of the programming world while refactoring is even smaller. The cause of this is the inability of developers to convince themselves and their managers that writing tests is beneficial. At the moment they are mostly viewed as waste of time. This is because the average person (let’s not fool ourselves, we’re all average) is unable to think about lower future costs in relation to little more current work. It’s orders of magnitude easier to know about the current costs in relation to current amount of work. That’s why programmers convince themselves testing is a waste of time. However we have to ask ourselves what tests are really about? Maybe finding bugs? No, not really. If we introduce bugs, we’re likely to write test around those bugs too. But yes we can find some bugs with tests. The main point of tests is to have reproducible repeatability in our systems. By having a code base largely covered by tests we can know with better certainty what a small code change can break in other parts of the system. By having repeatability we can make code changes with confidence, since we know we’ll see what breaks in other tests. And here comes the inability to estimate future costs. By spending just a few more hours writing those tests we’d know instantly what broke where. Imagine we fix a reported bug. We check-in the code, deploy it and the users are happy. Until we get a call 2 weeks later about a certain monthly process has stopped working. What we don’t know is that this process was developed by a long gone coworker and for some reason it relied on that same bug we’ve happily fixed. There’s no way we could’ve known that. We say OK and go in and fix the monthly process. But what we have no clue about is that there’s this ETL job that relied on data from that monthly process. Now that we’ve fixed the process it’s giving unexpected (yet correct since we fixed it) data to the ETL job. So we have to fix that too. But there’s this part of the app we coded that relies on data from that exact ETL job. And just like that we enter the “Loop of maintenance horror”. With the loop eventually comes blame. Here’s a nice tip for all developers and DBAs out there: If you make a mistake man up and admit to it. All of the above is valid for any kind of software development. Keeping this in mind the database is nothing other than just a part of the application. But a big part! One reason why testing a database is even more important than testing an application is that one database is usually accessed from multiple applications and processes. This makes it the central and vital part of the enterprise software infrastructure. Knowing all this can we really afford not to have tests? What to test in a database Now that we’ve decided we’ll dive into this testing thing we have to ask ourselves what needs to be tested? The short answer is: everything. The long answer is: read on! There are 2 main ways of doing tests: Black box and White box testing. Black box testing means we have no idea how the system internals are built and we only have access to it’s inputs and outputs. With it we test that the internal changes to the system haven’t caused the input/output behavior of the system to change. The most important thing to test here are the edge conditions. It’s where most programs break. Having good edge condition tests we can be more confident that the systems changes won’t break. White box testing has the full knowledge of the system internals. With it we test the internal system changes, different states of the application, etc… White and Black box tests should be complementary to each other as they are very much interconnected. Testing database routines includes testing stored procedures, views, user defined functions and anything you use to access the data with. Database routines are your input/output interface to the database system. They count as black box testing. We test then for 2 things: Data and schema. When testing schema we only care about the columns and the data types they’re returning. After all the schema is the contract to the out side systems. If it changes we usually have to change the applications accessing it. One helpful T-SQL command when doing schema tests is SET FMTONLY ON. It tells the SQL Server to return only empty results sets. This speeds up tests because it doesn’t return any data to the client. After we’ve validated the schema we have to test the returned data. There no other way to do this but to have expected data known before the tests executes and comparing that data to the database routine output. Testing Authentication and Authorization helps us validate who has access to the SQL Server box (Authentication) and who has access to certain database objects (Authorization). For desktop applications and windows authentication this works well. But the biggest problem here are web apps. They usually connect to the database as a single user. Please ensure that that user is not SA or an account with admin privileges. That is just bad. Load testing ensures us that our database can handle peak loads. One often overlooked tool for load testing is Microsoft’s OSTRESS tool. It’s part of RML utilities (x86, x64) for SQL Server and can help determine if our database server can handle loads like 100 simultaneous users each doing 10 requests per second. SQL Profiler can also help us here by looking at why certain queries are slow and what to do to fix them.   One particular problem to think about is how to begin testing existing databases. First thing we have to do is to get to know those databases. We can’t test something when we don’t know how it works. To do this we have to talk to the users of the applications accessing the database, run SQL Profiler to see what queries are being run, use existing documentation to decipher all the object relationships, etc… The way to approach this is to choose one part of the database (say a logical grouping of tables that go together) and filter our traces accordingly. Once we’ve done that we move on to the next grouping and so on until we’ve covered the whole database. Then we move on to the next one. Database Testing is a topic that we can spent many hours discussing but let this be a nice intro to the world of database testing. See you in the next post.

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• Refactoring a Single Rails Model with large methods & long join queries trying to do everything

  - by Kelseydh

  I have a working Ruby on Rails Model that I suspect is inefficient, hard to maintain, and full of unnecessary SQL join queries. I want to optimize and refactor this Model (Quiz.rb) to comply with Rails best practices, but I'm not sure how I should do it. The Rails app is a game that has Missions with many Stages. Users complete Stages by answering Questions that have correct or incorrect Answers. When a User tries to complete a stage by answering questions, the User gets a Quiz entry with many Attempts. Each Attempt records an Answer submitted for that Question within the Stage. A user completes a stage or mission by getting every Attempt correct, and their progress is tracked by adding a new entry to the UserMission & UserStage join tables. All of these features work, but unfortunately the Quiz.rb Model has been twisted to handle almost all of it exclusively. The callbacks began at 'Quiz.rb', and because I wasn't sure how to leave the Quiz Model during a multi-model update, I resorted to using Rails Console to have the @quiz instance variable via self.some_method do all the heavy lifting to retrieve every data value for the game's business logic; resulting in large extended join queries that "dance" all around the Database schema. The Quiz.rb Model that Smells: class Quiz < ActiveRecord::Base belongs_to :user has_many :attempts, dependent: :destroy before_save :check_answer before_save :update_user_mission_and_stage accepts_nested_attributes_for :attempts, :reject_if => lambda { |a| a[:answer_id].blank? }, :allow_destroy => true #Checks every answer within each quiz, adding +1 for each correct answer #within a stage quiz, and -1 for each incorrect answer def check_answer stage_score = 0 self.attempts.each do |attempt| if attempt.answer.correct? == true stage_score += 1 elsif attempt.answer.correct == false stage_score - 1 end end stage_score end def winner return true end def update_user_mission_and_stage ####### #Step 1: Checks if UserMission exists, finds or creates one. #if no UserMission for the current mission exists, creates a new UserMission if self.user_has_mission? == false @user_mission = UserMission.new(user_id: self.user.id, mission_id: self.current_stage.mission_id, available: true) @user_mission.save else @user_mission = self.find_user_mission end ####### #Step 2: Checks if current UserStage exists, stops if true to prevent duplicate entry if self.user_has_stage? @user_mission.save return true else ####### ##Step 3: if step 2 returns false: ##Initiates UserStage creation instructions #checks for winner (winner actions need to be defined) if they complete last stage of last mission for a given orientation if self.passed? && self.is_last_stage? && self.is_last_mission? create_user_stage_and_update_user_mission self.winner #NOTE: The rest are the same, but specify conditions that are available to add badges or other actions upon those conditions occurring: ##if user completes first stage of a mission elsif self.passed? && self.is_first_stage? && self.is_first_mission? create_user_stage_and_update_user_mission #creates user badge for finishing first stage of first mission self.user.add_badge(5) self.user.activity_logs.create(description: "granted first-stage badge", type_event: "badge", value: "first-stage") #If user completes last stage of a given mission, creates a new UserMission elsif self.passed? && self.is_last_stage? && self.is_first_mission? create_user_stage_and_update_user_mission #creates user badge for finishing first mission self.user.add_badge(6) self.user.activity_logs.create(description: "granted first-mission badge", type_event: "badge", value: "first-mission") elsif self.passed? create_user_stage_and_update_user_mission else self.passed? == false return true end end end #Creates a new UserStage record in the database for a successful Quiz question passing def create_user_stage_and_update_user_mission @nu_stage = @user_mission.user_stages.new(user_id: self.user.id, stage_id: self.current_stage.id) @nu_stage.save @user_mission.save self.user.add_points(50) end #Boolean that defines passing a stage as answering every question in that stage correct def passed? self.check_answer >= self.number_of_questions end #Returns the number of questions asked for that stage's quiz def number_of_questions self.attempts.first.answer.question.stage.questions.count end #Returns the current_stage for the Quiz, routing through 1st attempt in that Quiz def current_stage self.attempts.first.answer.question.stage end #Gives back the position of the stage relative to its mission. def stage_position self.attempts.first.answer.question.stage.position end #will find the user_mission for the current user and stage if it exists def find_user_mission self.user.user_missions.find_by_mission_id(self.current_stage.mission_id) end #Returns true if quiz was for the last stage within that mission #helpful for triggering actions related to a user completing a mission def is_last_stage? self.stage_position == self.current_stage.mission.stages.last.position end #Returns true if quiz was for the first stage within that mission #helpful for triggering actions related to a user completing a mission def is_first_stage? self.stage_position == self.current_stage.mission.stages_ordered.first.position end #Returns true if current user has a UserMission for the current stage def user_has_mission? self.user.missions.ids.include?(self.current_stage.mission.id) end #Returns true if current user has a UserStage for the current stage def user_has_stage? self.user.stages.include?(self.current_stage) end #Returns true if current user is on the last mission based on position within a given orientation def is_first_mission? self.user.missions.first.orientation.missions.by_position.first.position == self.current_stage.mission.position end #Returns true if current user is on the first stage & mission of a given orientation def is_last_mission? self.user.missions.first.orientation.missions.by_position.last.position == self.current_stage.mission.position end end My Question Currently my Rails server takes roughly 500ms to 1 sec to process single @quiz.save action. I am confident that the slowness here is due to sloppy code, not bad Database ERD design. What does a better solution look like? And specifically: Should I use join queries to retrieve values like I did here, or is it better to instantiate new objects within the model instead? Or am I missing a better solution? How should update_user_mission_and_stage be refactored to follow best practices? Relevant Code for Reference: quizzes_controller.rb w/ Controller Route Initiating Callback: class QuizzesController < ApplicationController before_action :find_stage_and_mission before_action :find_orientation before_action :find_question def show end def create @user = current_user @quiz = current_user.quizzes.new(quiz_params) if @quiz.save if @quiz.passed? if @mission.next_mission.nil? && @stage.next_stage.nil? redirect_to root_path, notice: "Congratulations, you have finished the last mission!" elsif @stage.next_stage.nil? redirect_to [@mission.next_mission, @mission.first_stage], notice: "Correct! Time for Mission #{@mission.next_mission.position}", info: "Starting next mission" else redirect_to [@mission, @stage.next_stage], notice: "Answer Correct! You passed the stage!" end else redirect_to [@mission, @stage], alert: "You didn't get every question right, please try again." end else redirect_to [@mission, @stage], alert: "Sorry. We were unable to save your answer. Please contact the admministrator." end @questions = @stage.questions.all end private def find_stage_and_mission @stage = Stage.find(params[:stage_id]) @mission = @stage.mission end def find_question @question = @stage.questions.find_by_id params[:id] end def quiz_params params.require(:quiz).permit(:user_id, :attempt_id, {attempts_attributes: [:id, :quiz_id, :answer_id]}) end def find_orientation @orientation = @mission.orientation @missions = @orientation.missions.by_position end end Overview of Relevant ERD Database Relationships: Mission - Stage - Question - Answer - Attempt <- Quiz <- User Mission - UserMission <- User Stage - UserStage <- User Other Models: Mission.rb class Mission < ActiveRecord::Base belongs_to :orientation has_many :stages has_many :user_missions, dependent: :destroy has_many :users, through: :user_missions #SCOPES scope :by_position, -> {order(position: :asc)} def stages_ordered stages.order(:position) end def next_mission self.orientation.missions.find_by_position(self.position.next) end def first_stage next_mission.stages_ordered.first end end Stage.rb: class Stage < ActiveRecord::Base belongs_to :mission has_many :questions, dependent: :destroy has_many :user_stages, dependent: :destroy has_many :users, through: :user_stages accepts_nested_attributes_for :questions, reject_if: :all_blank, allow_destroy: true def next_stage self.mission.stages.find_by_position(self.position.next) end end Question.rb class Question < ActiveRecord::Base belongs_to :stage has_many :answers, dependent: :destroy accepts_nested_attributes_for :answers, :reject_if => lambda { |a| a[:body].blank? }, :allow_destroy => true end Answer.rb: class Answer < ActiveRecord::Base belongs_to :question has_many :attempts, dependent: :destroy end Attempt.rb: class Attempt < ActiveRecord::Base belongs_to :answer belongs_to :quiz end User.rb: class User < ActiveRecord::Base belongs_to :school has_many :activity_logs has_many :user_missions, dependent: :destroy has_many :missions, through: :user_missions has_many :user_stages, dependent: :destroy has_many :stages, through: :user_stages has_many :orientations, through: :school has_many :quizzes, dependent: :destroy has_many :attempts, through: :quizzes def latest_stage_position self.user_missions.last.user_stages.last.stage.position end end UserMission.rb class UserMission < ActiveRecord::Base belongs_to :user belongs_to :mission has_many :user_stages, dependent: :destroy end UserStage.rb class UserStage < ActiveRecord::Base belongs_to :user belongs_to :stage belongs_to :user_mission end

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• The Great Divorce

  - by BlackRabbitCoder

  I have a confession to make: I've been in an abusive relationship for more than 17 years now.  Yes, I am not ashamed to admit it, but I'm finally doing something about it. I met her in college, she was new and sexy and amazingly fast -- and I'd never met anything like her before.  Her style and her power captivated me and I couldn't wait to learn more about her.  I took a chance on her, and though I learned a lot from her -- and will always be grateful for my time with her -- I think it's time to move on. Her name was C++, and she so outshone my previous love, C, that any thoughts of going back evaporated in the heat of this new romance.  She promised me she'd be gentle and not hurt me the way C did.  She promised me she'd clean-up after herself better than C did.  She promised me she'd be less enigmatic and easier to keep happy than C was.  But I was deceived.  Oh sure, as far as truth goes, it wasn't a complete lie.  To some extent she was more fun, more powerful, safer, and easier to maintain.  But it just wasn't good enough -- or at least it's not good enough now. I loved C++, some part of me still does, it's my first-love of programming languages and I recognize its raw power, its blazing speed, and its improvements over its predecessor.  But with today's hardware, at speeds we could only dream to conceive of twenty years ago, that need for speed -- at the cost of all else -- has died, and that has left my feelings for C++ moribund. If I ever need to write an operating system or a device driver, then I might need that speed.  But 99% of the time I don't.  I'm a business-type programmer and chances are 90% of you are too, and even the ones who need speed at all costs may be surprised by how much you sacrifice for that.   That's not to say that I don't want my software to perform, and it's not to say that in the business world we don't care about speed or that our job is somehow less difficult or technical.  There's many times we write programs to handle millions of real-time updates or handle thousands of financial transactions or tracking trading algorithms where every second counts.  But if I choose to write my code in C++ purely for speed chances are I'll never notice the speed increase -- and equally true chances are it will be far more prone to crash and far less easy to maintain.  Nearly without fail, it's the macro-optimizations you need, not the micro-optimizations.  If I choose to write a O(n2) algorithm when I could have used a O(n) algorithm -- that can kill me.  If I choose to go to the database to load a piece of unchanging data every time instead of caching it on first load -- that too can kill me.  And if I cross the network multiple times for pieces of data instead of getting it all at once -- yes that can also kill me.  But choosing an overly powerful and dangerous mid-level language to squeeze out every last drop of performance will realistically not make stock orders process any faster, and more likely than not open up the system to more risk of crashes and resource leaks. And that's when my love for C++ began to die.  When I noticed that I didn't need that speed anymore.  That that speed was really kind of a lie.  Sure, I can be super efficient and pack bits in a byte instead of using separate boolean values.  Sure, I can use an unsigned char instead of an int.  But in the grand scheme of things it doesn't matter as much as you think it does.  The key is maintainability, and that's where C++ failed me.  I like to tell the other developers I work with that there's two levels of correctness in coding: Is it immediately correct? Will it stay correct? That is, you can hack together any piece of code and make it correct to satisfy a task at hand, but if a new developer can't come in tomorrow and make a fairly significant change to it without jeopardizing that correctness, it won't stay correct. Some people laugh at me when I say I now prefer maintainability over speed.  But that is exactly the point.  If you focus solely on speed you tend to produce code that is much harder to maintain over the long hall, and that's a load of technical debt most shops can't afford to carry and end up completely scrapping code before it's time.  When good code is written well for maintainability, though, it can be correct both now and in the future. And you know the best part is?  My new love is nearly as fast as C++, and in some cases even faster -- and better than that, I know C# will treat me right.  Her creators have poured hundreds of thousands of hours of time into making her the sexy beast she is today.  They made her easy to understand and not an enigmatic mess.  They made her consistent and not moody and amorphous.  And they made her perform as fast as I care to go by optimizing her both at compile time and a run-time. Her code is so elegant and easy on the eyes that I'm not worried where she will run to or what she'll pull behind my back.  She is powerful enough to handle all my tasks, fast enough to execute them with blazing speed, maintainable enough so that I can rely on even fairly new peers to modify my work, and rich enough to allow me to satisfy any need.  C# doesn't ask me to clean up her messes!  She cleans up after herself and she tries to make my life easier for me by taking on most of those optimization tasks C++ asked me to take upon myself.  Now, there are many of you who would say that I am the cause of my own grief, that it was my fault C++ didn't behave because I didn't pay enough attention to her.  That I alone caused the pain she inflicted on me.  And to some extent, you have a point.  But she was so high maintenance, requiring me to know every twist and turn of her vast and unrestrained power that any wrong term or bout of forgetfulness was met with painful reminders that she wasn't going to watch my back when I made a mistake.  But C#, she loves me when I'm good, and she loves me when I'm bad, and together we make beautiful code that is both fast and safe. So that's why I'm leaving C++ behind.  She says she's changing for me, but I have no interest in what C++0x may bring.  Oh, I'll still keep in touch, and maybe I'll see her now and again when she brings her problems to my door and asks for some attention -- for I always have a soft spot for her, you see.  But she's out of my house now.  I have three kids and a dog and a cat, and all require me to clean up after them, why should I have to clean up after my programming language as well?

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• How to Never Use iTunes With Your iPhone, iPad, or iPod Touch

  - by Chris Hoffman

  iTunes isn’t an amazing program on Windows. There was a time when Apple device users had to plug their devices into their PCs or Macs and use iTunes for device activation, updates, and syncing, but iTunes is no longer necessary. Apple still allows you to use iTunes for these things, but you don’t have to. Your iOS device can function independently from iTunes, so you should never be forced to plug it into a PC or Mac. Device Activation When the iPad first came out, it was touted as a device that could replace full PCs and Macs for people who only needed to perform light computing tasks. Yet, to set up a new iPad, users had to plug it into a PC or Mac running iTunes and use iTunes to activate the device. This is no longer necessary. With new iPads, iPhones, and iPod Touches, you can simply go through the setup process after turning on your new device without ever having to plug it into iTunes. Just connect to a Wi-Fi or cellular data network and log in with your Apple ID when prompted. You’ll still see an option that allows you to activate the device via iTunes, but this should only be necessary if you don’t have a wireless Internet connection available for your device. Operating System Updates You no longer have to use Apple’s iTunes software to update to a new version of Apple’s iOS operating system, either. Just open the Settings app on your device, select the General category, and tap Software Update. You’ll be able to update right from your device without ever opening iTunes. Purchased iTunes Media Apple allows you to easily access content you’ve purchased from the iTunes Store on any device. You don’t have to connect your device to your computer and sync via iTunes. For example, you can purchase a movie from the iTunes Store. Then, without any syncing, you can open the iTunes Store app on any of your iOS devices, tap the Purchased section, and see stuff you’ve downloaded. You can download the content right from the store to your device. This also works for apps — apps you purchase from the App Store can be accessed in the Purchased section on the App Store on your device later. You don’t have to sync apps from iTunes to your device, although iTunes still allows you to. You can even set up automatic downloads from the iTunes & App Store settings screen. This would allow you to purchase content on one device and have it automatically download to your other devices without any hassle. Music Apple allows you to re-download purchased music from the iTunes Store in the same way. However, there’s a good chance you have your own music you didn’t purchase from iTunes. Maybe you spent time ripping it all from your old CDs and you’ve been syncing it to your devices via iTunes ever since. Apple’s solution for this is named iTunes Match. This feature isn’t free, but it’s not a bad deal at all. For $25 per year, Apple allows you to upload all your music to your iCloud account. You can then access all your music from any iPhone, IPad, or iPod Touch. You can stream all your music — perfect if you have a huge library and little storage on your device — and choose which songs you want to download to your device for offline use. When you add additional music to your computer, iTunes will notice it and upload it using iTunes Match, making it available for streaming and downloading directly from your iOS devices without any syncing. This feature is named iTunes Match because it doesn’t just upload music — if Apple already has a song you upload, it will “match” your song with Apple’s copy. This means you may get higher-quality versions of your songs if you ripped them from CD at a lower bitrate. Podcasts You don’t have to use iTunes to subscribe to podcasts and sync them to your devices. Even if you have a lowly iPod Touch, you can install APple’s Podcasts app from the app store. Use it to subscribe to podcasts and configure them to automatically download directly to your device. You can use other podcast apps for this, too. Backups You can continue backing up your device’s data through iTunes, generating local backups that are stored on your computer. However, new iOS devices are configured to automatically back up their data to iCloud. This happens automatically in the background without you even having to think about it, and you can restore such backups when setting up a device simply by logging in with your Apple ID. Personal Data In the days of PalmPilots, people would use desktop programs like iTunes to sync their email, contacts, and calendar events with their mobile devices. You probably shouldn’t have to sync this data form your computer. Just sign into your email account — for example, a Gmail account — on your device and iOS will automatically pull your email, contacts, and calendar events from your associated account. Photos Rather than connecting your iOS device to your computer and syncing photos from it, you can use an app that automatically uploads your photos to a web service. Dropbox, Google+, and even Flickr all have this feature in their apps. You’ll be able to access your photos from any computer and have a backup copy without any syncing required. You may still need to use iTunes if you want to sync local music without paying for iTunes Match or copy local video files to your device. Copying large local files over is the only real scenario where you’d need iTunes. If you don’t need to copy such files over, you can go ahead and uninstall iTunes from your Windows PC if you like. You shouldn’t need it.     

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• Thoughts on Build 2013

  - by D'Arcy Lussier

  Originally posted on: http://geekswithblogs.net/dlussier/archive/2013/06/30/153294.aspxAnd so another Build conference has come to an end. Below are my thoughts/perspectives on various aspects of the event. I’ll do a separate blog post on my thoughts of the Build message for developers. The Good Moscone center was a great venue for Build! Easy to get around, easy to get to, and well maintained, it was a very comfortable conference venue. Yeah, the free swag was nice. Build has built up an expectation that attendees will always get something; it’ll be interesting to see how Microsoft maintains this expectation over the next few Build events. I still maintain that free swag should never be the main reason one attends an event, and for me this was definitely just an added bonus. I’m planning on trying to use the Surface as a dedicated 2nd device at work for meetings, I’ll share my experiences over the next few months. The hackathon event was a great idea, although personally I couldn’t justify spending the money on a conference registration just to spend the entire conference coding. Still, the apps that were created were really great and there was a lot of passion and excitement around the hackathon. I wonder if they couldn’t have had the hackathon on the Monday/Tuesday for those that wanted to participate so they didn’t miss any of the actual conference over Wed/Thurs. San Francisco was a great city to host Build. Getting from hotels to the conference center was very easy (well especially for me, I was only 3 blocks away) and the city itself felt very safe. However, if I never have to fly into SFO again I’ll be alright with that! Delays going into and out of SFO and both apparently were due to the airport itself. The Bad Build is one of those oddities on the conference landscape where people will pay to commit to attending an event without knowing anything about the sessions. We got our list of conference sessions when we registered on Tuesday, not before. And even then, we only got titles and not descriptions (those were eventually made available via the conference’s mobile application). I get it…they’re going to make announcements and they don’t want to give anything away through the session titles. But honestly, there wasn’t anything in the session titles that I would have considered a surprise. Breakfasts were brutal. High-carb pastries, donuts, and muffins with fruit and hard boiled eggs does not a conference breakfast make. I can’t believe that the difference between a continental breakfast per person and a hot breakfast buffet would have been a huge impact to a conference fee that was already around $2000. The vendor area was anemic. I don’t know why Microsoft forces the vendors into cookie-cutter booth areas (this year they were all made of plywood material). WPC, TechEd – booth areas there allow the vendors to be creative with their displays. Not so much for Build. Really odd was the lack of Microsoft’s own representation around Bing. In the day 1 keynote Microsoft made a big deal about Bing as an API. Yet there was nobody in the vendor area set up to provide more information or have discussions with about the Bing API. The Ugly Our name badges were NFC enabled. The purpose of this, beyond the vendors being able to scan your info, wasn’t really made clear. An attendee I talked to showed how you could get a reader app on your phone so you can scan other members cards and collect their contact info – which is a kewl idea; business cards are so 1990’s. But I was *shocked* at the amount of information that was on our name badges! Here’s what’s displayed on our name badge: - Name - Company - Twitter Handle I’m ok with that. But here’s what actually gets read: - Name - Company - Address Used for Registration - Phone Number Used for Registration So sharing that info with another attendee, they get way more of my info than just how to find me on Twitter! Microsoft, you need to fix this for the future. If vendors want to collect information on attendees, they should be able to collect an ID from the badge, then get a report with corresponding records afterwards. My personal information should not be so readily available, and without my knowledge! Final Verdict Maybe its my older age, maybe its where I’m at in life with family, maybe its where I’m at in my career, but when I consider whether a conference experience was valuable I get to the core reason I attend: opportunities to learn, opportunities to network, opportunities to engage with Microsoft. Opportunities to Learn:  Sessions I attended were generally OK, with some really stand out ones on Day 2. I would love to see Microsoft adopt the Dojo format for a portion of their sessions. Hands On Labs are dull, lecture style sessions are great for information sharing. But a guided hands-on coding session (Read: Dojo) provides the best of both worlds. Being that all content is publically available online to everyone (Build attendee or not), the value of attending the conference sessions is decreased. The value though is in the discussions that take part in person afterwards, which leads to… Opportunities to Network: I enjoyed getting together with old friends and connecting with Twitter friends in person for the first time. I also had an opportunity to meet total strangers. So from a networking perspective, Build was fantastic! I still think it would have been great to have an area for ad-hoc discussions – where speakers could announce they’d be available for more questions after their sessions, or attendees who wanted to discuss more in depth on a topic with other attendees could arrange space. Some people have no problems being outgoing and making these things happen, but others are not and a structured model is more attractive. Opportunities to Engage with Microsoft: Hit and miss on this one. Outside of the vendor area, unless you cornered or reached out to a speaker, there wasn’t any defined way to connect with blue badges. And as I mentioned above, Microsoft didn’t have full representation in the vendor area (no Bing). All in all, Build was a fun party where I was informed about some new stuff and got some free swag. Was it worth the time away from home and the hit to my PD budget? I’d say Somewhat. Build is a great informational conference, but I wouldn’t call it a learning conference. Considering that TechEd seems to be moving to more of an IT Pro focus, independent developer conferences seem to be the best value for those looking to learn and not just be informed. With the rapid development cycle Microsoft is embracing, we’re already seeing Build happening twice within a 12 month period. If that continues, the value of attending Build in person starts to diminish – especially with so much content available online. If Microsoft wants Build to be a must-attend event in the future, they need to start incorporating aspects of Tech Ed, past PDCs, and other conferences so those that want to leave with more than free swag have something to attract them.

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• SQL SERVER – Windows File/Folder and Share Permissions – Notes from the Field #029

  - by Pinal Dave

  [Note from Pinal]: This is a 29th episode of Notes from the Field series. Security is the task which we should give it to the experts. If there is a small overlook or misstep, there are good chances that security of the organization is compromised. This is very true, but there are always devils’s advocates who believe everyone should know the security. As a DBA and Administrator, I often see people not taking interest in the Windows Security hiding behind the reason of not expert of Windows Server. We all often miss the important mission statement for the success of any organization – Teamwork. In this blog post Brian tells the story in very interesting lucid language. Read On! In this episode of the Notes from the Field series database expert Brian Kelley explains a very crucial issue DBAs and Developer faces on their production server. Linchpin People are database coaches and wellness experts for a data driven world. Read the experience of Brian in his own words. When I talk security among database professionals, I find that most have at least a working knowledge of how to apply security within a database. When I talk with DBAs in particular, I find that most have at least a working knowledge of security at the server level if we’re speaking of SQL Server. One area I see continually that is weak is in the area of Windows file/folder (NTFS) and share permissions. The typical response is, “I’m a database developer and the Windows system administrator is responsible for that.” That may very well be true – the system administrator may have the primary responsibility and accountability for file/folder and share security for the server. However, if you’re involved in the typical activities surrounding databases and moving data around, you should know these permissions, too. Otherwise, you could be setting yourself up where someone is able to get to data he or she shouldn’t, or you could be opening the door where human error puts bad data in your production system. File/Folder Permission Basics: I wrote about file/folder permissions a few years ago to give the basic permissions that are most often seen. Here’s what you must know as a minimum at the file/folder level: Read - Allows you to read the contents of the file or folder. Having read permissions allows you to copy the file or folder. Write  – Again, as the name implies, it allows you to write to the file or folder. This doesn’t include the ability to delete, however, nothing stops a person with this access from writing an empty file. Delete - Allows the file/folder to be deleted. If you overwrite files, you may need this permission. Modify - Allows read, write, and delete. Full Control - Same as modify + the ability to assign permissions. File/Folder permissions aggregate, unless there is a DENY (where it trumps, just like within SQL Server), meaning if a person is in one group that gives Read and antoher group that gives Write, that person has both Read and Write permissions. As you might expect me to say, always apply the Principle of Least Privilege. This likely means that any additional permission you might add does not need Full Control. Share Permission Basics: At the share level, here are the permissions. Read - Allows you to read the contents on the share. Change - Allows you to read, write, and delete contents on the share. Full control - Change + the ability to modify permissions. Like with file/folder permissions, these permissions aggregate, and DENY trumps. So What Access Does a Person / Process Have? Figuring out what someone or some process has depends on how the location is being accessed: Access comes through the share (\\ServerName\Share) – a combination of permissions is considered. Access is through a drive letter (C:\, E:\, S:\, etc.) – only the file/folder permissions are considered. The only complicated one here is access through the share. Here’s what Windows does: Figures out what the aggregated permissions are at the file/folder level. Figures out what the aggregated permissions are at the share level. Takes the most restrictive of the two sets of permissions. You can test this by granting Full Control over a folder (this is likely already in place for the Users local group) and then setting up a share. Give only Read access through the share, and that includes to Administrators (if you’re creating a share, likely you have membership in the Administrators group). Try to read a file through the share. Now try to modify it. The most restrictive permission is the Share level permissions. It’s set to only allow Read. Therefore, if you come through the share, it’s the most restrictive. Does This Knowledge Really Help Me? In my experience, it does. I’ve seen cases where sensitive files were accessible by every authenticated user through a share. Auditors, as you might expect, have a real problem with that. I’ve also seen cases where files to be imported as part of the nightly processing were overwritten by files intended from development. And I’ve seen cases where a process can’t get to the files it needs for a process because someone changed the permissions. If you know file/folder and share permissions, you can spot and correct these types of security flaws. Given that there are a lot of database professionals that don’t understand these permissions, if you know it, you set yourself apart. And if you’re able to help on critical processes, you begin to set yourself up as a linchpin (link to .pdf) for your organization. If you want to get started with performance tuning and database security with the help of experts, read more over at Fix Your SQL Server. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: Notes from the Field, PostADay, SQL, SQL Authority, SQL Query, SQL Security, SQL Server, SQL Tips and Tricks, T SQL

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• Moving from Tortoise to TFS

  - by MarkPearl

  The Past A few years ago my small software company made the jump from storing code on a shared folder to source code control. At the time we had evaluated a few of the options and settled on Tortoise SVN. The main motivation for going the SVN route was that we found a great plugin for Visual Studio that allowed us to avoid the command prompt for uploading changes (like I said we are windows programmers… command prompt bad!! ) and it was free. Up to now we have been pretty happy with SVN as it removed many of the worries that I had about how safe my code was on a shared folder and also gave us the opportunity to safely have several developers work on the same project at the same time. The only times when we have been unhappy has been when we have had SVN hell days – which pretty much occur when you are doing something out of the norm and suddenly SVN just won’t resolve conflicts or something along those lines. This happens once every 4 or 5 months and is not necessarily a problem caused directly by SVN – but a problem augmented by SVN. When you have SVN hell days you want to curse SVN! With that in mind I recently have been relooking at our source code control. I have explored using GIT and was very impressed by it and have also looked at TFS. From a source code control perspective I don’t want to get into a heated discussion on which one is better – but I do want to mention that I wear two hats in my organization – software developer & manager, and with the manager hat on I tend to sway the TFS route. So when I was given a coupon to test DiscountASP.Net Team Foundation Server Service for a year, I thought it was the perfect opportunity to try TFS in a distributed environment and also make the first step towards having an integrated development management system. Some of the things that appeal to me about DiscountASP’s offering are the following… Basic management / planning facilities like to do lists inside Visual Studio Daily backup of data on the server – we are developers, not IT managers and so the more of this I could outsource the better Distributed solution – all of us work remotely and so this was a big one as well. Registering and Setting Up with DiscountASP.NET The whole registration process was simple and intuitive. The web interface is not the most visually impressive one, but it is functional and a few seconds after I clicked the last submit button a email was sitting in my inbox giving me my control panel username and suggesting that I read the “Getting Started” article. The getting started article was easy to read and understand so no complaints there either. Next to set my dev environment to work. With a few references to the getting started article I had completed the whole setup process in a matter of minutes. Ten minutes after initiating the whole thing I was logged into VS2010 and creating my first TFS project. With the service that I signed up for, I have access for 5 users – which is sufficient for my internal needs. So from what I can tell, to set the rest of us up on the system I just need to supply them with their user credentials and url. My Concerns Resolved 1) Security So, a few concerns I had about the service. First and foremost – is it secure? I would hate for someone to get access to our code and the whole idea of putting it up on the internet is a concern for me. Turning to the Knowledge Base on the DiscountASP website this is one of the first question I can see answered. According to them it is secure. I have extracted their comment below regarding this. Our TFS hosting service is secure. We only accept HTTPS connections ensuring that any client-server data transmission is encrypted. At the network level, all of our systems are protected by multiple Juniper firewalls, Tipping Point's Intrusion Detection System (see Tipping Point's case study of our use here), and we also employ DDoS mitigation to add extra layers of security. Additionally, physical access to the servers is tightly restricted. Please see the security section of this Knowledge Base article for further details. 2) Web Portal Access The other big concern I have is regarding web portal access. In the ideal world I would like to be able to give my end users access to a web portal for reporting bugs etc. When I initially read through the FAQ of the site it mentioned that there was web portal access – but from what I can see this is just for “users”. Since I am limited to 5 users for the account, it would not be practical to set up external users that we could get feedback from on bugs etc. I would be interested if this is possible – and if so if someone could post it in the comments it would be much appreciated. If this isn’t possible, it is a slight let down as we rely heavily on end user feedback to get feedback and it would have been ideal to have gotten this within the service. Other than those two items, I didn’t have any real concerns that were unresolved. So where do I go from here? So time passed by from the initial writing of this post and as work whirred in and out of my inbox I have still not had a proper opportunity to give the service a test run. Recently though things have began to slow down and then surprise surprise I had another SVN Hell day. With that experience I had a new found resolve to get our team on TFS and so today we are going to start to use the service as a team. I am hoping that I do not have TFS hell days – but if I do, I will be sure to write about them. In short - the verdict is still out on whether this service is going to be invaluable to my business or whether it will create more headaches than it is worth BUT I am hopping it will be an invaluable service. I will only really be able to determine that in a few months… till then!

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• Christmas in the Clouds

  - by andrewbrust

  I have been spending the last 2 weeks immersing myself in a number of Windows Azure and SQL Azure technologies.  And in setting up a new business (I’ll speak more about that in the future), I have also become a customer of Microsoft’s BPOS (Business Productivity Online Services).  In short, it has been a fortnight of Microsoft cloud computing. On the Azure side, I’ve looked, of course, at Web Roles and Worker Roles.  But I’ve also looked at Azure Storage’s REST API (including coding to it directly), I’ve looked at Azure Drive and the new VM Role; I’ve looked quite a bit at SQL Azure (including the project “Houston” Silverlight UI) and I’ve looked at SQL Azure labs’ OData service too. I’ve also looked at DataMarket and its integration with both PowerPivot and native Excel.  Then there’s AppFabric Caching, SQL Azure Reporting (what I could learn of it) and the Visual Studio tooling for Azure, including the storage of certificate-based credentials.  And to round it out with some user stuff, on the BPOS side, I’ve been working with Exchange Online, SharePoint Online and LiveMeeting. I have to say I like a lot of what I’ve been seeing.  Azure’s not perfect, and BPOS certainly isn’t either.  But there’s good stuff in all these products, and there’s a lot of value. Azure Goes Deep Most people know that Web and Worker roles put the platform in charge of spinning virtual machines up and down, and keeping them up to date. But you can go way beyond that now.  The still-in-beta VM Role gives you the power to craft the machine (much as does Amazon’s EC2), though it takes away the platform’s self-managing attributes.  It still spins instances up and down, making drive storage non-durable, but Azure Drive gives you the ability to store VHD files as blobs and mount them as virtual hard drives that are readable and writeable.  Whether with Azure Storage or SQL Azure, Azure does data.  And OData is everywhere.  Azure Table Storage supports an OData Interface.  So does SQL Azure and so does DataMarket (the former project “Dallas”).  That means that Azure data repositories aren’t just straightforward to provision and configure…they’re also easy to program against, from just about any programming environment, in a RESTful manner.  And for more .NET-centric implementations, Azure AppFabric caching takes the technology formerly known as “Velocity” and throws it up into the cloud, speeding data access even more. Snapping in Place Once you get the hang of it, this stuff just starts to work in a way that becomes natural to understand.  I wasn’t expecting that, and I was really happy to discover it. In retrospect, I am not surprised, because I think the various Azure teams are the center of gravity for Redmond’s innovation right now.  The products belie this and so do my observations of the product teams’ motivation and high morale.  It is really good to see this; Microsoft needs to lead somewhere, and they need to be seen as the underdog while doing so.  With Azure, both requirements are in place.   BPOS: Bad Acronym, Easy Setup BPOS is about products you already know; Exchange, SharePoint, Live Meeting and Office Communications Server.  As such, it’s hard not to be underwhelmed by BPOS.  Until you realize how easy it makes it to get all that stuff set up.  I would say that from sign-up to productive use took me about 45 minutes…and that included the time necessary to wrestle with my DNS provider, set up Outlook and my SmartPhone up to talk to the Exchange account, create my SharePoint site collection, and configure the Outlook Conferencing add-in to talk to the provisioned Live Meeting account. Never before did I think setting up my own Exchange mail could come anywhere close to the simplicity of setting up an SMTP/POP account, and yet BPOS actually made it faster.   What I want from my Azure Christmas Next Year Not everything about Microsoft’s cloud is good.  I close this post with a list of things I’d like to see addressed: BPOS offerings are still based on the 2007 Wave of Microsoft server technologies.  We need to get to 2010, and fast.  Arguably, the 2010 products should have been released to the off-premises channel before the on-premise sone.  Office 365 can’t come fast enough. Azure’s Internet tooling and domain naming, is scattered and confusing.  Deployed ASP.NET applications go to cloudapp.net; SQL Azure and Azure storage work off windows.net.  The Azure portal and Project Houston are at azure.com.  Then there’s appfabriclabs.com and sqlazurelabs.com.  There is a new Silverlight portal that replaces most, but not all of the HTML ones.  And Project Houston is Silvelright-based too, though separate from the Silverlight portal tooling. Microsoft is the king off tooling.  They should not make me keep an entire OneNote notebook full of portal links, account names, access keys, assemblies and namespaces and do so much CTRL-C/CTRL-V work.  I’d like to see more project templates, have them automatically reference the appropriate assemblies, generate the right using/Imports statements and prime my config files with the right markup.  Then I want a UI that lets me log in with my Live ID and pick the appropriate project, database, namespace and key string to get set up fast. Beta programs, if they’re open, should onboard me quickly.  I know the process is difficult and everyone’s going as fast as they can.  But I don’t know why it’s so difficult or why it takes so long.  Getting developers up to speed on new features quickly helps popularize the platform.  Make this a priority. Make Azure accessible from the simplicity platforms, i.e. ASP.NET Web Pages (Razor) and LightSwitch.  Support .NET 4 now.  Make WebMatrix, IIS Express and SQL Compact work with the Azure development fabric. Have HTML helpers make Azure programming easier.  Have LightSwitch work with SQL Azure and not require SQL Express.  LightSwitch has some promising Azure integration now.  But we need more.  WebMatrix has none and that’s just silly, now that the Extra Small Instance is being introduced. The Windows Azure Platform Training Kit is great.  But I want Microsoft to make it even better and I want them to evangelize it much more aggressively.  There’s a lot of good material on Azure development out there, but it’s scattered in the same way that the platform is.   The Training Kit ties a lot of disparate stuff together nicely.  Make it known. Should Old Acquaintance Be Forgot All in all, diving deep into Azure was a good way to end the year.  Diving deeper into Azure should a great way to spend next year, not just for me, but for Microsoft too.

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