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• Analysing and measuring the performance of a .NET application (survey results)

  - by Laila

  Back in December last year, I asked myself: could it be that .NET developers think that you need three days and a PhD to do performance profiling on their code? What if developers are shunning profilers because they perceive them as too complex to use? If so, then what method do they use to measure and analyse the performance of their .NET applications? Do they even care about performance? So, a few weeks ago, I decided to get a 1-minute survey up and running in the hopes that some good, hard data would clear the matter up once and for all. I posted the survey on Simple Talk and got help from a few people to promote it. The survey consisted of 3 simple questions: Amazingly, 533 developers took the time to respond - which means I had enough data to get representative results! So before I go any further, I would like to thank all of you who contributed, because I now have some pretty good answers to the troubling questions I was asking myself. To thank you properly, I thought I would share some of the results with you. First of all, application performance is indeed important to most of you. In fact, performance is an intrinsic part of the development cycle for a good 40% of you, which is much higher than I had anticipated, I have to admit. (I know, "Have a little faith Laila!") When asked what tool you use to measure and analyse application performance, I found that nearly half of the respondents use logging statements, a third use performance counters, and 70% of respondents use a profiler of some sort (a 3rd party performance profilers, the CLR profiler or the Visual Studio profiler). The importance attributed to logging statements did surprise me a little. I am still not sure why somebody would go to the trouble of manually instrumenting code in order to measure its performance, instead of just using a profiler. I personally find the process of annotating code, calculating times from log files, and relating it all back to your source terrifyingly laborious. Not to mention that you then need to remember to turn it all off later! Even when you have logging in place throughout all your code anyway, you still have a fair amount of potentially error-prone calculation to sift through the results; in addition, you'll only get method-level rather than line-level timings, and you won't get timings from any framework or library methods you don't have source for. To top it all, we all know that bottlenecks are rarely where you would expect them to be, so you could be wasting time looking for a performance problem in the wrong place. On the other hand, profilers do all the work for you: they automatically collect the CPU and wall-clock timings, and present the results from method timing all the way down to individual lines of code. Maybe I'm missing a trick. I would love to know about the types of scenarios where you actively prefer to use logging statements. Finally, while a third of the respondents didn't have a strong opinion about code performance profilers, those who had an opinion thought that they were mainly complex to use and time consuming. Three respondents in particular summarised this perfectly: "sometimes, they are rather complex to use, adding an additional time-sink to the process of trying to resolve the existing problem". "they are simple to use, but the results are hard to understand" "Complex to find the more advanced things, easy to find some low hanging fruit". These results confirmed my suspicions: Profilers are seen to be designed for more advanced users who can use them effectively and make sense of the results. I found yet more interesting information when I started comparing samples of "developers for whom performance is an important part of the dev cycle", with those "to whom performance is only looked at in times of crisis", and "developers to whom performance is not important, as long as the app works". See the three graphs below. Sample of developers to whom performance is an important part of the dev cycle: Sample of developers to whom performance is important only in times of crisis: Sample of developers to whom performance is not important, as long as the app works: As you can see, there is a strong correlation between the usage of a profiler and the importance attributed to performance: indeed, the more important performance is to a development team, the more likely they are to use a profiler. In addition, developers to whom performance is an important part of the dev cycle have a higher tendency to use a much wider range of methods for performance measurement and analysis. And, unsurprisingly, the less important performance is, the less varied the methods of measurement are. So all in all, to come back to my random questions: .NET developers do care about performance. Those who care the most use a wider range of performance measurement methods than those who care less. But overall, logging statements, performance counters and third party performance profilers are the performance measurement methods of choice for most developers. Finally, although most of you find code profilers complex to use, those of you who care the most about performance tend to use profilers more than those of you to whom performance is not so important.

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• Passing the CAML thru the EY of the NEEDL

  - by PointsToShare

  © 2011 By: Dov Trietsch. All rights reserved Passing the CAML thru the EY of the NEEDL Definitions: CAML (Collaborative Application Markup Language) is an XML based markup language used in Microsoft SharePoint technologies  Anonymous: A camel is a horse designed by committee  Dov Trietsch: A CAML is a HORS designed by Microsoft  I was advised against putting any Camel and Sphinx rhymes in here. Look it up in Google!  _____ Now that we have dispensed with the dromedary jokes (BTW, I have many more, but they are not fit to print!), here is an interesting problem and its solution.  We have built a list where the title must be kept unique so I needed to verify the existence (or absence) of a list item with a particular title. Two methods came to mind:  1: Span the list until the title is found (result = found) or until the list ends (result = not found). This is an algorithm of complexity O(N) and for long lists it is a performance sucker. 2: Use a CAML query instead. Here, for short list we’ll encounter some overhead, but because the query results in an SQL query on the content database, it is of complexity O(LogN), which is significantly better and scales perfectly. Obviously I decided to go with the latter and this is where the CAML s--t hit the fan.   A CAML query returns a SPListItemCollection and I simply checked its Count. If it was 0, the item did not already exist and it was safe to add a new item with the given title. Otherwise I cancelled the operation and warned the user. The trouble was that I always got a positive. Most of the time a false positive. The count was greater than 0 regardles of the title I checked (except when the list was empty, which happens only once). This was very disturbing indeed. To solve my immediate problem which was speedy delivery, I reverted to the “Span the list” approach, but the problem bugged me, so I wrote a little console app by which I tested and tweaked and tested, time and again, until I found the solution. Yes, one can pass the proverbial CAML thru the ey of the needle (e’s missing on purpose).  So here are my conclusions:  CAML that does not work:  Note: QT is my quote:  char QT = Convert.ToChar((int)34); string titleQuery = "<Query>><Where><Eq>"; titleQuery += "<FieldRef Name=" + QT + "Title" + QT + "/>"; titleQuery += "<Value Type=" + QT + "Text" + QT + ">" + uniqueID + "</Value></Eq></Where></Query>"; titleQuery += "<ViewFields><FieldRef Name=" + QT + "Title" + QT + "/></ViewFields>";  Why? Even though U2U generates it, the <Query> and </Query> tags do not belong in the query that you pass. Start your query with the <Where> clause.  Also the <ViewFiels> clause does not belong. I used this clause to limit the returned collection to a single column, and I still wish to do it. I’ll show how this is done a bit later.   When you use the <Query> </Query> tags in you query, it’s as if you did not specify the query at all. What you get is the all inclusive default query for the list. It returns evey column and every item. It is expensive for both server and network because it does all the extra processing and eats plenty of bandwidth.   Now, here is the CAML that works  string titleQuery = "<Where><Eq>"; titleQuery += "<FieldRef Name=" + QT + "Title" + QT + "/>"; titleQuery += "<Value Type=" + QT + "Text" + QT + ">" + uniqueID + "</Value></Eq></Where>";  You’ll also notice that inside the unusable <ViewFields> clause above, we have a <FieldRef> clause. This is what we pass to the SPQuery object. Here is how:  SPQuery query = new SPQuery(); query.Query = titleQuery; query.ViewFields = "<FieldRef Name=" + QT + "Title" + QT + "/>"; query.RowLimit = 1; SPListItemCollection col = masterList.GetItems(query);  Two thing to note: we enter the view fields into the SPQuery object and we also limited the number of rows that the query returns. The latter is not always done, but in an existence test, there is no point in returning hundreds of rows. The query will now return one item or none, which is all we need in order to verify the existence (or non-existence) of items. Limiting the number of columns and the number of rows is a great performance enhancer. That’s all folks!!

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• SQL SERVER – The Story of a Lesser Known Startup Parameter in SQL Server – Guest Post by Balmukund Lakhani

  - by Pinal Dave

  This is a fantastic blog post from my dear friend Balmukund ( blog | twitter | facebook ). He had presented a fantastic session in our last UG and there were lots of requests from attendees that he blogs about it. Well, here is the blog post about the same very popular UG session. Let us read the entire blog post in the voice of the Balmukund himself. During my last session in SQL Bangalore User Group (Facebook) meeting, I was lucky enough to deliver a session on SQL Server Startup issue. The name of the session was “SQL Engine Starting Trouble – How to start?” From the feedback, I realized that one of the “not well known” startup parameter is “-m”. Okay, you might say “I know that this is used to start the SQL in single user mode”. But what you might not know is that you can pass a string with -m which has special meaning and use. I have used this parameter in my blog here but looks like not many of you have seen that. It happens most of the time when we want to start SQL Server in single user mode, someone else makes connection before you can. The only choice you have is to repeat same process again till you succeed. Some smart DBAs may disable the remote network protocols (TCP/IP and Named Pipes) of SQL Instance and allow only local connections to SQL. Once the activity is complete, our dear smart DBA has to remember to re-enable network protocols. Sometimes, it may be a local service or application getting connection to SQL before we can. There is a better way to deal with it. Yes, you have guessed it correctly: -m parameter which a string. Since I work with SQL Product Support team, I may know little more undocumented commands and parameters, but this is not an undocumented stuff. It’s already documented in books online. So in this blog, I am going to show a demo of its usage. As documentation shows, “Do not use this option as a security feature.” So please read this blog as knowledge enhancer and troubleshooting issues not security feature. In my laptop, I have a default instance of SQL Server 2012 and here is what we would in the configuration manager. Now, I would go ahead and stop SQL Service by selecting SQL Server (MSSQLServer) > Right Click > Stop. There are multiple ways to start SQL with startup parameter. 1) Use Net Start Command from command prompt Net Start MSSQLServer /mSQLCMD The above command is the simplest way to add startup parameter to SQL. This parameter would be cleared once we stop and start SQL. 2) Add Startup Parameter via configuration manager. Step is already listed here. We need to add -mSQLCMD If we compare 1 and 2, it’s clear that unless we modify startup parameter and remove -m, it would be in effect. 3) Start SQL Service via command line SQLServr.exe –mSQLCMD –s<InstanceName> Wait, what does SQLCMD mean with /m? It’s the instruction to SQL that start SQL Server in Single User Mode and allow only the application which is SQLCMD. Any other application would fail with Login Failed for User Error message. It would be important to note that string is case sensitive. This value should be picked up from application_name column from sys.dm_exec_sessions. I have made a connection using SQLCMD and as we can see it comes as upper case “SQLCMD”. If we want only management studio query windows to connect then we need to give -m” Microsoft SQL Server Management Studio – Query” as startup parameter. In below example, I have given it as SQLCMd (lower case d at the end) and we would notice that we would not be able to connect to SQL Instance. Above proves that parameter works as expected and it’s case sensitive. Error Log would show below information. How to get error log location? I have already blogged about it. Hope you have learned something new. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Server Management Studio, SQL Tips and Tricks, T SQL, Technology

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• Atmospheric Scattering

  - by Lawrence Kok

  I'm trying to implement atmospheric scattering based on Sean O`Neil algorithm that was published in GPU Gems 2. But I have some trouble getting the shader to work. My latest attempts resulted in: http://img253.imageshack.us/g/scattering01.png/ I've downloaded sample code of O`Neil from: http://http.download.nvidia.com/developer/GPU_Gems_2/CD/Index.html. Made minor adjustments to the shader 'SkyFromAtmosphere' that would allow it to run in AMD RenderMonkey. In the images it is see-able a form of banding occurs, getting an blueish tone. However it is only applied to one half of the sphere, the other half is completely black. Also the banding appears to occur at Zenith instead of Horizon, and for a reason I managed to get pac-man shape. I would appreciate it if somebody could show me what I'm doing wrong. Vertex Shader: uniform mat4 matView; uniform vec4 view_position; uniform vec3 v3LightPos; const int nSamples = 3; const float fSamples = 3.0; const vec3 Wavelength = vec3(0.650,0.570,0.475); const vec3 v3InvWavelength = 1.0f / vec3( Wavelength.x * Wavelength.x * Wavelength.x * Wavelength.x, Wavelength.y * Wavelength.y * Wavelength.y * Wavelength.y, Wavelength.z * Wavelength.z * Wavelength.z * Wavelength.z); const float fInnerRadius = 10; const float fOuterRadius = fInnerRadius * 1.025; const float fInnerRadius2 = fInnerRadius * fInnerRadius; const float fOuterRadius2 = fOuterRadius * fOuterRadius; const float fScale = 1.0 / (fOuterRadius - fInnerRadius); const float fScaleDepth = 0.25; const float fScaleOverScaleDepth = fScale / fScaleDepth; const vec3 v3CameraPos = vec3(0.0, fInnerRadius * 1.015, 0.0); const float fCameraHeight = length(v3CameraPos); const float fCameraHeight2 = fCameraHeight * fCameraHeight; const float fm_ESun = 150.0; const float fm_Kr = 0.0025; const float fm_Km = 0.0010; const float fKrESun = fm_Kr * fm_ESun; const float fKmESun = fm_Km * fm_ESun; const float fKr4PI = fm_Kr * 4 * 3.141592653; const float fKm4PI = fm_Km * 4 * 3.141592653; varying vec3 v3Direction; varying vec4 c0, c1; float scale(float fCos) { float x = 1.0 - fCos; return fScaleDepth * exp(-0.00287 + x*(0.459 + x*(3.83 + x*(-6.80 + x*5.25)))); } void main( void ) { // Get the ray from the camera to the vertex, and its length (which is the far point of the ray passing through the atmosphere) vec3 v3FrontColor = vec3(0.0, 0.0, 0.0); vec3 v3Pos = normalize(gl_Vertex.xyz) * fOuterRadius; vec3 v3Ray = v3CameraPos - v3Pos; float fFar = length(v3Ray); v3Ray = normalize(v3Ray); // Calculate the ray's starting position, then calculate its scattering offset vec3 v3Start = v3CameraPos; float fHeight = length(v3Start); float fDepth = exp(fScaleOverScaleDepth * (fInnerRadius - fCameraHeight)); float fStartAngle = dot(v3Ray, v3Start) / fHeight; float fStartOffset = fDepth*scale(fStartAngle); // Initialize the scattering loop variables float fSampleLength = fFar / fSamples; float fScaledLength = fSampleLength * fScale; vec3 v3SampleRay = v3Ray * fSampleLength; vec3 v3SamplePoint = v3Start + v3SampleRay * 0.5; // Now loop through the sample rays for(int i=0; i<nSamples; i++) { float fHeight = length(v3SamplePoint); float fDepth = exp(fScaleOverScaleDepth * (fInnerRadius - fHeight)); float fLightAngle = dot(normalize(v3LightPos), v3SamplePoint) / fHeight; float fCameraAngle = dot(normalize(v3Ray), v3SamplePoint) / fHeight; float fScatter = (-fStartOffset + fDepth*( scale(fLightAngle) - scale(fCameraAngle)))/* 0.25f*/; vec3 v3Attenuate = exp(-fScatter * (v3InvWavelength * fKr4PI + fKm4PI)); v3FrontColor += v3Attenuate * (fDepth * fScaledLength); v3SamplePoint += v3SampleRay; } // Finally, scale the Mie and Rayleigh colors and set up the varying variables for the pixel shader vec4 newPos = vec4( (gl_Vertex.xyz + view_position.xyz), 1.0); gl_Position = gl_ModelViewProjectionMatrix * vec4(newPos.xyz, 1.0); gl_Position.z = gl_Position.w * 0.99999; c1 = vec4(v3FrontColor * fKmESun, 1.0); c0 = vec4(v3FrontColor * (v3InvWavelength * fKrESun), 1.0); v3Direction = v3CameraPos - v3Pos; } Fragment Shader: uniform vec3 v3LightPos; varying vec3 v3Direction; varying vec4 c0; varying vec4 c1; const float g =-0.90f; const float g2 = g * g; const float Exposure =2; void main(void){ float fCos = dot(normalize(v3LightPos), v3Direction) / length(v3Direction); float fMiePhase = 1.5 * ((1.0 - g2) / (2.0 + g2)) * (1.0 + fCos*fCos) / pow(1.0 + g2 - 2.0*g*fCos, 1.5); gl_FragColor = c0 + fMiePhase * c1; gl_FragColor.a = 1.0; }

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• Why lock-free data structures just aren't lock-free enough

  - by Alex.Davies

  Today's post will explore why the current ways to communicate between threads don't scale, and show you a possible way to build scalable parallel programming on top of shared memory. The problem with shared memory Soon, we will have dozens, hundreds and then millions of cores in our computers. It's inevitable, because individual cores just can't get much faster. At some point, that's going to mean that we have to rethink our architecture entirely, as millions of cores can't all access a shared memory space efficiently. But millions of cores are still a long way off, and in the meantime we'll see machines with dozens of cores, struggling with shared memory. Alex's tip: The best way for an application to make use of that increasing parallel power is to use a concurrency model like actors, that deals with synchronisation issues for you. Then, the maintainer of the actors framework can find the most efficient way to coordinate access to shared memory to allow your actors to pass messages to each other efficiently. At the moment, NAct uses the .NET thread pool and a few locks to marshal messages. It works well on dual and quad core machines, but it won't scale to more cores. Every time we use a lock, our core performs an atomic memory operation (eg. CAS) on a cell of memory representing the lock, so it's sure that no other core can possibly have that lock. This is very fast when the lock isn't contended, but we need to notify all the other cores, in case they held the cell of memory in a cache. As the number of cores increases, the total cost of a lock increases linearly. A lot of work has been done on "lock-free" data structures, which avoid locks by using atomic memory operations directly. These give fairly dramatic performance improvements, particularly on systems with a few (2 to 4) cores. The .NET 4 concurrent collections in System.Collections.Concurrent are mostly lock-free. However, lock-free data structures still don't scale indefinitely, because any use of an atomic memory operation still involves every core in the system. A sync-free data structure Some concurrent data structures are possible to write in a completely synchronization-free way, without using any atomic memory operations. One useful example is a single producer, single consumer (SPSC) queue. It's easy to write a sync-free fixed size SPSC queue using a circular buffer*. Slightly trickier is a queue that grows as needed. You can use a linked list to represent the queue, but if you leave the nodes to be garbage collected once you're done with them, the GC will need to involve all the cores in collecting the finished nodes. Instead, I've implemented a proof of concept inspired by this intel article which reuses the nodes by putting them in a second queue to send back to the producer. * In all these cases, you need to use memory barriers correctly, but these are local to a core, so don't have the same scalability problems as atomic memory operations. Performance tests I tried benchmarking my SPSC queue against the .NET ConcurrentQueue, and against a standard Queue protected by locks. In some ways, this isn't a fair comparison, because both of these support multiple producers and multiple consumers, but I'll come to that later. I started on my dual-core laptop, running a simple test that had one thread producing 64 bit integers, and another consuming them, to measure the pure overhead of the queue. So, nothing very interesting here. Both concurrent collections perform better than the lock-based one as expected, but there's not a lot to choose between the ConcurrentQueue and my SPSC queue. I was a little disappointed, but then, the .NET Framework team spent a lot longer optimising it than I did. So I dug out a more powerful machine that Red Gate's DBA tools team had been using for testing. It is a 6 core Intel i7 machine with hyperthreading, adding up to 12 logical cores. Now the results get more interesting. As I increased the number of producer-consumer pairs to 6 (to saturate all 12 logical cores), the locking approach was slow, and got even slower, as you'd expect. What I didn't expect to be so clear was the drop-off in performance of the lock-free ConcurrentQueue. I could see the machine only using about 20% of available CPU cycles when it should have been saturated. My interpretation is that as all the cores used atomic memory operations to safely access the queue, they ended up spending most of the time notifying each other about cache lines that need invalidating. The sync-free approach scaled perfectly, despite still working via shared memory, which after all, should still be a bottleneck. I can't quite believe that the results are so clear, so if you can think of any other effects that might cause them, please comment! Obviously, this benchmark isn't realistic because we're only measuring the overhead of the queue. Any real workload, even on a machine with 12 cores, would dwarf the overhead, and there'd be no point worrying about this effect. But would that be true on a machine with 100 cores? Still to be solved. The trouble is, you can't build many concurrent algorithms using only an SPSC queue to communicate. In particular, I can't see a way to build something as general purpose as actors on top of just SPSC queues. Fundamentally, an actor needs to be able to receive messages from multiple other actors, which seems to need an MPSC queue. I've been thinking about ways to build a sync-free MPSC queue out of multiple SPSC queues and some kind of sign-up mechanism. Hopefully I'll have something to tell you about soon, but leave a comment if you have any ideas.

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• DBCC CHECKDB (BatmanDb, REPAIR_ALLOW_DATA_LOSS) &ndash; Are you Feeling Lucky?

  - by David Totzke

  I’m currently working for a client on a PowerBuilder to WPF migration.  It’s one of those “I could tell you, but I’d have to kill you” kind of clients and the quick-lime pits are currently occupied by the EMC tech…but I’ve said too much already. At approximately 3 or 4 pm that day users of the Batman[1] application here in Gotham[1] started to experience problems accessing the application.  Batman[2] is a document management system here that also integrates with the ERP system.  Very little goes on here that doesn’t involve Batman in some way.  The errors being received seemed to point to network issues (TCP protocol error, connection forcibly closed by the remote host etc…) but the real issue was much more insidious. Connecting to the database via SSMS and performing selects on certain tables underlying the application areas that were having problems started to reveal the issue.  You couldn’t do a SELECT * FROM MyTable without it bombing and giving the same error noted above.  A run of DBCC CHECKDB revealed 14 tables with corruption.  One of the tables with issues was the Document table.  Pretty central to a “document management” system.  Information was obtained from IT that a single drive in the SAN went bad in the night.  A new drive was in place and was working fine.  The partition that held the Batman database is configured for RAID Level 5 so a single drive failure shouldn’t have caused any trouble and yet, the database is corrupted.  They do hourly incremental backups here so the first thing done was to try a restore.  A restore of the most recent backup failed so they worked backwards until they hit a good point.  This successful restore was for a backup at 3AM – a full day behind.  This time also roughly corresponds with the time the SAN started to report the drive failure.  The plot thickens… I got my hands on the output from DBCC CHECKDB and noticed a pattern.  What’s sad is that nobody that should have noticed the pattern in the DBCC output did notice.  There was a rush to do things to try and recover the data before anybody really understood what was wrong with it in the first place.  Cooler heads must prevail in these circumstances and some investigation should be done and a plan of action laid out or you could end up making things worse[3].  DBCC CHECKDB also told us that: repair_allow_data_loss is the minimum repair level for the errors found by DBCC CHECKDB Yikes.  That means that the database is so messed up that you’re definitely going to lose some stuff when you repair it to get it back to a consistent state.  All the more reason to do a little more investigation into the problem.  Rescuing this database is preferable to having to export all of the data possible from this database into a new one.  This is a fifteen year old application with about seven hundred tables.  There are TRIGGERS everywhere not to mention the referential integrity constraints to deal with.  Only fourteen of the tables have an issue.  We have a good backup that is missing the last 24 hours of business which means we could have a “do-over” of yesterday but that’s not a very palatable option either. All of the affected tables had TEXT columns and all of the errors were about LOB data types and orphaned off-row data which basically means TEXT, IMAGE or NTEXT columns.  If we did a SELECT on an affected table and excluded those columns, we got all of the rows.  We exported that data into a separate database.  Things are looking up.  Working on a copy of the production database we then ran DBCC CHECKDB with REPAIR_ALLOW_DATA_LOSS and that “fixed” everything up.   The allow data loss option will delete the bad rows.  This isn’t too horrible as we have all of those rows minus the text fields from out earlier export.  Now I could LEFT JOIN to the exported data to find the missing rows and INSERT them minus the TEXT column data. We had the restored data from the good 3AM backup that we could now JOIN to and, with fingers crossed, recover the missing TEXT column information.  We got lucky in that all of the affected rows were old and in the end we didn’t lose anything.  :O  All of the row counts along the way worked out and it looks like we dodged a major bullet here. We’ve heard back from EMC and it turns out the SAN firmware that they were running here is apparently buggy.  This thing is only a couple of months old.  Grrr…. They dispatched a technician that night to come and update it .  That explains why RAID didn’t save us. All-in-all this could have been a lot worse.  Given the root cause here, they basically won the lottery in not losing anything. Here are a few links to some helpful posts on the SQL Server Engine blog.  I love the title of the first one: Which part of 'REPAIR_ALLOW_DATA_LOSS' isn't clear? CHECKDB (Part 8): Can repair fix everything? (in fact, read the whole series) Ta da! Emergency mode repair (we didn’t have to resort to this one thank goodness)   Dave Just because I can…   [1] Names have been changed to protect the guilty. [2] I'm Batman. [3] And if I'm the coolest head in the room, you've got even bigger problems...

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• Bring Office 2003 Menus Back to 2010 with UBitMenu

  - by Matthew Guay

  Are you having trouble getting used to the Ribbon interface in Office 2010?  Here’s how you can roll back the clock a bit and bring back the familiar menus and toolbars from 2003. The Office 2007 Ribbon was both praised and criticized.  While many users felt they were more productive with the new interface, others felt frustrated searching for commands they had memorized in older versions of Office.  Now, with Office 2010, the ribbon interface has been brought to every app in the Office suite, and is integrated into many newer programs from Microsoft. If you’re moving from Office 2003, using UBitMenu allows you to add the old familiar menus back along with the new Ribbon interface for an easier learning curve. Also, with the customizability of Office 2010, we can strip away the extra Ribbon tabs to make it more like 2003. Get the 2003 Menus and Toolbars Back in Office 2010 Download UBitMenu (link below), and install as normal.  Make sure all of your Office programs are closed during the installation.  This handy utility is very small, and installed amazingly quick. Open Word, Excel, or PowerPoint and there’s now a new Menu tab beside Home in the Ribbon.  Now you can access all of your favorite old Office commands in the familiar menus, and access many of the newer Office features such as SmartArt.   Here’s a close-up of the toolbar.  Notice that the layout is very similar to that of Word 2003. You can access all of the new Transitions in PowerPoint 2010 from the menu bar.   The menu in Excel even included support for the new PivotTable and PivotCharts Wizard. One problem we noticed was that the toolbars were condensed to a drop-down menu if the Office window was less than 870px wide.  This may be a frustration to users with low-resolution displays, and you might want to use the Office Apps maximized. Get Rid of the Ribbon Now that you’ve got the old menus back, you can get rid of the extra ribbon tabs if you’d like.  Office 2010 lets you customize your ribbon and remove tabs, so let’s get rid of all the other tabs except for our new Menu tab.  In our example we’re using Word, but you can do it in Excel or PowerPoint the same way. Click the File tab and select Options. Alternately, in the Menu tab, select Tools and then Word Options. Select Customize Ribbon on the left sidebar, then uncheck the boxes beside all the ribbon tabs you want to hide on the right.  Click Ok when you’re finished. While you’re at it, you can change the default color scheme as well. Note: The color change will automatically change the color scheme in all of the Office apps, so you’ll only need to do that once. Now the ribbon only has 2 tabs…the File tab for the new Backstage View, and the UBitMenu tab we just installed.  It almost has the appearance Word 2003, but with the new features of Word 2010!  You’ll need to repeat these steps in Excel and PowerPoint if you want to customize their ribbon the same.   Conclusion If you’ve been having a hard time getting used to Office 2010, UBitMenu is a great way to get familiar with the new interface, or simply stay productive with your old tricks.  We do wish it supported the other Office applications like OneNote and Outlook. That doesn’t make it a deal breaker though, it can make the learning curve easier in Word, PowerPoint, and Excel. UBitMenu is free for personal use, and available at a very reasonable price for businesses. If you’re using Office 2007 and not a fan of the Ribbon, UBitMenu works for it as well. Download UBitMenu Similar Articles Productive Geek Tips How To Bring Back the Old Menus in Office 2007Upgrade Office 2003 to 2010 on XP or Run them Side by SideHow to Find Office 2003 Commands in Office 2010Make Word 2007 Always Save in Word 2003 FormatMake Excel 2007 Always Save in Excel 2003 Format TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips HippoRemote Pro 2.2 Xobni Plus for Outlook All My Movies 5.9 CloudBerry Online Backup 1.5 for Windows Home Server Speed Up Windows With ReadyBoost Awesome World Cup Soccer Calendar Nice Websites To Watch TV Shows Online 24 Million Sites Windows Media Player Glass Icons (icons we like) How to Forecast Weather, without Gadgets

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• Cant get lm-sensors to load ATI Radeon temp or fan

  - by woody

  New to Linux and having minor issues :/ . I followed this guide initially but did not recieve the proper output and did not show my ATI Radeon HD 5000 temp or fan speed. Then used this guide, same problems exhibited. No issues installing and no errors. I think its not reading i2c for some reason. The proprietary driver is installed and functioning correctly according fglrxinfo. I can use aticonfig commands and view both temp and fan. Any ideas on how to get it working under 'sensors'? When i run 'sudo sensors-detect' this is my ouput # sensors-detect revision 5984 (2011-07-10 21:22:53 +0200) # System: LENOVO IdeaPad Y560 (laptop) # Board: Lenovo KL3 This program will help you determine which kernel modules you need to load to use lm_sensors most effectively. It is generally safe and recommended to accept the default answers to all questions, unless you know what you're doing. Some south bridges, CPUs or memory controllers contain embedded sensors. Do you want to scan for them? This is totally safe. (YES/no): y Silicon Integrated Systems SIS5595... No VIA VT82C686 Integrated Sensors... No VIA VT8231 Integrated Sensors... No AMD K8 thermal sensors... No AMD Family 10h thermal sensors... No AMD Family 11h thermal sensors... No AMD Family 12h and 14h thermal sensors... No AMD Family 15h thermal sensors... No AMD Family 15h power sensors... No Intel digital thermal sensor... Success! (driver `coretemp') Intel AMB FB-DIMM thermal sensor... No VIA C7 thermal sensor... No VIA Nano thermal sensor... No Some Super I/O chips contain embedded sensors. We have to write to standard I/O ports to probe them. This is usually safe. Do you want to scan for Super I/O sensors? (YES/no): y Probing for Super-I/O at 0x2e/0x2f Trying family `National Semiconductor/ITE'... Yes Found unknown chip with ID 0x8502 Probing for Super-I/O at 0x4e/0x4f Trying family `National Semiconductor/ITE'... No Trying family `SMSC'... No Trying family `VIA/Winbond/Nuvoton/Fintek'... No Trying family `ITE'... No Some hardware monitoring chips are accessible through the ISA I/O ports. We have to write to arbitrary I/O ports to probe them. This is usually safe though. Yes, you do have ISA I/O ports even if you do not have any ISA slots! Do you want to scan the ISA I/O ports? (YES/no): y Probing for `National Semiconductor LM78' at 0x290... No Probing for `National Semiconductor LM79' at 0x290... No Probing for `Winbond W83781D' at 0x290... No Probing for `Winbond W83782D' at 0x290... No Lastly, we can probe the I2C/SMBus adapters for connected hardware monitoring devices. This is the most risky part, and while it works reasonably well on most systems, it has been reported to cause trouble on some systems. Do you want to probe the I2C/SMBus adapters now? (YES/no): y Using driver `i2c-i801' for device 0000:00:1f.3: Intel 3400/5 Series (PCH) Now follows a summary of the probes I have just done. Just press ENTER to continue: Driver `coretemp': * Chip `Intel digital thermal sensor' (confidence: 9) To load everything that is needed, add this to /etc/modules: #----cut here---- # Chip drivers coretemp #----cut here---- If you have some drivers built into your kernel, the list above will contain too many modules. Skip the appropriate ones! Do you want to add these lines automatically to /etc/modules? (yes/NO) My output for 'sensors' is: acpitz-virtual-0 Adapter: Virtual device temp1: +58.0°C (crit = +100.0°C) coretemp-isa-0000 Adapter: ISA adapter Core 0: +56.0°C (high = +84.0°C, crit = +100.0°C) Core 1: +57.0°C (high = +84.0°C, crit = +100.0°C) Core 2: +58.0°C (high = +84.0°C, crit = +100.0°C) Core 3: +57.0°C (high = +84.0°C, crit = +100.0°C) and my '/etc/modules' is: # /etc/modules: kernel modules to load at boot time. # # This file contains the names of kernel modules that should be loaded # at boot time, one per line. Lines beginning with "#" are ignored. lp rtc # Generated by sensors-detect on Fri Nov 30 23:24:31 2012 # Chip drivers coretemp

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• texture mapping with lib3ds and SOIL help

  - by Adam West

  I'm having trouble with my project for loading a texture map onto a model. Any insight into what is going wrong with my code is fantastic. Right now the code only renders a teapot which I have assinged after creating it in 3DS Max. 3dsloader.cpp #include "3dsloader.h" Object::Object(std:: string filename) { m_TotalFaces = 0; m_model = lib3ds_file_load(filename.c_str()); // If loading the model failed, we throw an exception if(!m_model) { throw strcat("Unable to load ", filename.c_str()); } // set properties of texture coordinate generation for both x and y coordinates glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR); glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR); // if not already enabled, enable texture generation if(! glIsEnabled(GL_TEXTURE_GEN_S)) glEnable(GL_TEXTURE_GEN_S); if(! glIsEnabled(GL_TEXTURE_GEN_T)) glEnable(GL_TEXTURE_GEN_T); } Object::~Object() { if(m_model) // if the file isn't freed yet lib3ds_file_free(m_model); //free up memory glDisable(GL_TEXTURE_GEN_S); glDisable(GL_TEXTURE_GEN_T); } void Object::GetFaces() { m_TotalFaces = 0; Lib3dsMesh * mesh; // Loop through every mesh. for(mesh = m_model->meshes;mesh != NULL;mesh = mesh->next) { // Add the number of faces this mesh has to the total number of faces. m_TotalFaces += mesh->faces; } } void Object::CreateVBO() { assert(m_model != NULL); // Calculate the number of faces we have in total GetFaces(); // Allocate memory for our vertices and normals Lib3dsVector * vertices = new Lib3dsVector[m_TotalFaces * 3]; Lib3dsVector * normals = new Lib3dsVector[m_TotalFaces * 3]; Lib3dsTexel* texCoords = new Lib3dsTexel[m_TotalFaces * 3]; Lib3dsMesh * mesh; unsigned int FinishedFaces = 0; // Loop through all the meshes for(mesh = m_model->meshes;mesh != NULL;mesh = mesh->next) { lib3ds_mesh_calculate_normals(mesh, &normals[FinishedFaces*3]); // Loop through every face for(unsigned int cur_face = 0; cur_face < mesh->faces;cur_face++) { Lib3dsFace * face = &mesh->faceL[cur_face]; for(unsigned int i = 0;i < 3;i++) { memcpy(&texCoords[FinishedFaces*3 + i], mesh->texelL[face->points[ i ]], sizeof(Lib3dsTexel)); memcpy(&vertices[FinishedFaces*3 + i], mesh->pointL[face->points[ i ]].pos, sizeof(Lib3dsVector)); } FinishedFaces++; } } // Generate a Vertex Buffer Object and store it with our vertices glGenBuffers(1, &m_VertexVBO); glBindBuffer(GL_ARRAY_BUFFER, m_VertexVBO); glBufferData(GL_ARRAY_BUFFER, sizeof(Lib3dsVector) * 3 * m_TotalFaces, vertices, GL_STATIC_DRAW); // Generate another Vertex Buffer Object and store the normals in it glGenBuffers(1, &m_NormalVBO); glBindBuffer(GL_ARRAY_BUFFER, m_NormalVBO); glBufferData(GL_ARRAY_BUFFER, sizeof(Lib3dsVector) * 3 * m_TotalFaces, normals, GL_STATIC_DRAW); // Generate a third VBO and store the texture coordinates in it. glGenBuffers(1, &m_TexCoordVBO); glBindBuffer(GL_ARRAY_BUFFER, m_TexCoordVBO); glBufferData(GL_ARRAY_BUFFER, sizeof(Lib3dsTexel) * 3 * m_TotalFaces, texCoords, GL_STATIC_DRAW); // Clean up our allocated memory delete vertices; delete normals; delete texCoords; // We no longer need lib3ds lib3ds_file_free(m_model); m_model = NULL; } void Object::applyTexture(const char*texfilename) { float imageWidth; float imageHeight; glGenTextures(1, & textureObject); // allocate memory for one texture textureObject = SOIL_load_OGL_texture(texfilename,SOIL_LOAD_AUTO,SOIL_CREATE_NEW_ID,SOIL_FLAG_MIPMAPS); glPixelStorei(GL_UNPACK_ALIGNMENT,1); glBindTexture(GL_TEXTURE_2D, textureObject); // use our newest texture glGetTexLevelParameterfv(GL_TEXTURE_2D,0,GL_TEXTURE_WIDTH,&imageWidth); glGetTexLevelParameterfv(GL_TEXTURE_2D,0,GL_TEXTURE_HEIGHT,&imageHeight); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); // give the best result for texture magnification glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); //give the best result for texture minification glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP); // don't repeat texture glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP); // don't repeat textureglTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP); // don't repeat texture glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE,GL_MODULATE); glTexImage2D(GL_TEXTURE_2D,0,GL_RGB,imageWidth,imageHeight,0,GL_RGB,GL_UNSIGNED_BYTE,& textureObject); } void Object::Draw() const { // Enable vertex, normal and texture-coordinate arrays. glEnableClientState(GL_VERTEX_ARRAY); glEnableClientState(GL_NORMAL_ARRAY); glEnableClientState(GL_TEXTURE_COORD_ARRAY); // Bind the VBO with the normals. glBindBuffer(GL_ARRAY_BUFFER, m_NormalVBO); // The pointer for the normals is NULL which means that OpenGL will use the currently bound VBO. glNormalPointer(GL_FLOAT, 0, NULL); glBindBuffer(GL_ARRAY_BUFFER, m_TexCoordVBO); glTexCoordPointer(2, GL_FLOAT, 0, NULL); glBindBuffer(GL_ARRAY_BUFFER, m_VertexVBO); glVertexPointer(3, GL_FLOAT, 0, NULL); // Render the triangles. glDrawArrays(GL_TRIANGLES, 0, m_TotalFaces * 3); glDisableClientState(GL_VERTEX_ARRAY); glDisableClientState(GL_NORMAL_ARRAY); glDisableClientState(GL_TEXTURE_COORD_ARRAY); } 3dsloader.h #include "main.h" #include "lib3ds/file.h" #include "lib3ds/mesh.h" #include "lib3ds/material.h" class Object { public: Object(std:: string filename); virtual ~Object(); virtual void Draw() const; virtual void CreateVBO(); void applyTexture(const char*texfilename); protected: void GetFaces(); unsigned int m_TotalFaces; Lib3dsFile * m_model; Lib3dsMesh* Mesh; GLuint textureObject; GLuint m_VertexVBO, m_NormalVBO, m_TexCoordVBO; }; Called in the main cpp file with: VBO,apply texture and draw (pretty simple, how ironic) and thats it, please help me forum :)

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• Justifiable Perks.

  - by Phil Factor

      I was once the director of a start-up IT Company, and had the task of recruiting a proportion of the management team. As my background was in IT management, I was rather more familiar with recruiting Geeks for technology jobs, but here, one of my early tasks was interviewing a Marketing Director.  The small group of financiers had suggested a rather strange Irishman called  Halleran.  From my background in City of London dealing-rooms, I was slightly unprepared for the experience of interviewing anyone wearing a pink suit. Many of my older City colleagues would have required resuscitation after seeing his white leather shoes. However, nobody will accuse me of prejudging an interviewee. After all, many Linux experts who I’ve come to rely on have appeared for interview dressed as hobbits. In fact, the interview went well, and we had even settled his salary.  I was somewhat unprepared for the coda.    ‘And I will need to be provided with a Ferrari  by the company.’    ‘Hmm. That seems reasonable.’    Initially, he looked startled, and then a slow smile of victory spread across his face.    ‘What colour would you like?’ I asked genially.    ‘It has to be red.’ He looked very earnest on this point.    ‘Fine. I have to go past Hamleys on the way home this evening, so I’ll pick one up then for you.’    ‘Er.. Hamley’s is a toyshop, not a Ferrari Dealership.’    I stared at him in bafflement for a few seconds. ‘You’re not seriously asking for a real Ferrari are you?’     ‘Well, yes. Not for my own sake, you understand. I’d much prefer a simple run-about, but my position demands it. How could I maintain the necessary status in the office without one? How could I do my job in marketing when my grey Datsun was all too visible in the car Park? It is a tool of the job.’    ‘Excuse me a moment, but I must confer with the MD’    I popped out to see Chris, the MD. ‘Chris, I’m interviewing a lunatic in a pink suit who is trying to demand that a Ferrari is a precondition of his employment. I tried the ‘misunderstanding trick’ but it didn’t faze him.’     ‘Sorry, Phil, but we’ve got to hire him. The VCs insist on it. You’ve got to think of something that doesn’t involve committing to the purchase of a Ferrari. Current funding barely covers the rent for the building.’    ‘OK boss. Leave it to me.’    On return, I slapped O’Halleran’s file on the table with a genial, paternalistic smile. ‘Of course you should have a Ferrari. The only trouble is that it will require a justification document that can be presented to the board. I’m sure you’ll have no problem in preparing this document in the required format.’ The initial look of despair was quickly followed by a bland look of acquiescence. He had, earlier in the interview, argued with great eloquence his skill in preparing the tiresome documents that underpin the essential corporate and government deals that were vital to the success of this new enterprise. The justification of a Ferrari should be a doddle.     After the interview, Chris nervously asked how I’d fared.     ‘I think it is all solved.’    ‘… without promising a Ferrari, I hope.’    ‘Well, I did actually; on condition he justified it in writing.’    Chris issued a stream of invective. The strain of juggling the resources in an underfunded startup was beginning to show.    ‘Don’t worry. In the unlikely event of him coming back with the required document, I’ll give him mine.’    ‘Yours?’ He strode over to the window to stare down at the car park.    He needn’t have worried: I knew that his breed of marketing man could more easily lay an ostrich egg than to prepare a decent justification document. My Ferrari is still there at the back of my garage. Few know of the Ferrari cultivator, a simple inexpensive motorized device designed for the subsistence farmers of southern Italy. It is the very devil to start, but it creates a perfect tilth for the seedbed.

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• Using SQL Source Control with Fortress or Vault &ndash; Part 1

  - by AjarnMark

  I am fanatical when it comes to managing the source code for my company.  Everything that we build (in source form) gets put into our source control management system.  And I’m not just talking about the UI and middle-tier code written in C# and ASP.NET, but also the back-end database stuff, which at times has been a pain.  We even script out our Scheduled Jobs and keep a copy of those under source control. The UI and middle-tier stuff has long been easy to manage as we mostly use Visual Studio which has integration with source control systems built in.  But the SQL code has been a little harder to deal with.  I have been doing this for many years, well before Microsoft came up with Data Dude, so I had already established a methodology that, while not as smooth as VS, nonetheless let me keep things well controlled, and allowed doing my database development in my tool of choice, Query Analyzer in days gone by, and now SQL Server Management Studio.  It just makes sense to me that if I’m going to do database development, let’s use the database tool set.  (Although, I have to admit I was pretty impressed with the demo of Juneau that Don Box did at the PASS Summit this year.)  So as I was saying, I had developed a methodology that worked well for us (and I’ll probably outline in a future post) but it could use some improvement. When Solutions and Projects were first introduced in SQL Management Studio, I thought we were finally going to get our same experience that we have in Visual Studio.  Well, let’s say I was underwhelmed by Version 1 in SQL 2005, and apparently so were enough other people that by the time SQL 2008 came out, Microsoft decided that Solutions and Projects would be deprecated and completely removed from a future version.  So much for that idea. Then I came across SQL Source Control from Red-Gate.  I have used several tools from Red-Gate in the past, including my favorites SQL Compare, SQL Prompt, and SQL Refactor.  SQL Prompt is worth its weight in gold, and the others are great, too.  Earlier this year, we upgraded from our earlier product bundles to the new Developer Bundle, and in the process added SQL Source Control to our collection.  I thought this might really be the golden ticket I was looking for.  But my hopes were quickly dashed when I discovered that it only integrated with Microsoft Team Foundation Server and Subversion as the source code repositories.  We have been using SourceGear’s Vault and Fortress products for years, and I wholeheartedly endorse them.  So I was out of luck for the time being, although there were a number of people voting for Vault/Fortress support on their feedback forum (as did I) so I had hope that maybe next year I could look at it again. But just a couple of weeks ago, I was pleasantly surprised to receive notice in my email that Red-Gate had an Early Access version of SQL Source Control that worked with Vault and Fortress, so I quickly downloaded it and have been putting it through its paces.  So far, I really like what I see, and I have been quite impressed with Red-Gate’s responsiveness when I have contacted them with any issues or concerns that I have had.  I have had several communications with Gyorgy Pocsi at Red-Gate and he has been immensely helpful and responsive. I must say that development with SQL Source Control is very different from what I have been used to.  This post is getting long enough, so I’ll save some of the details for a separate write-up, but the short story is that in my regular mode, it’s all about the script files.  Script files are King and you dare not make a change to the database other than by way of a script file, or you are in deep trouble.  With SQL Source Control, you make your changes to your development database however you like.  I still prefer writing most of my changes in T-SQL, but you can also use any of the GUI functionality of SSMS to make your changes, and SQL Source Control “manages” the script for you.  Basically, when you first link your database to source control, the tool generates scripts for every primary object (tables and their indexes are together in one script, not broken out into separate scripts like DB Projects do) and those scripts are checked into your source control.  So, if you needed to, you could still do a GET from your source control repository and build the database from scratch.  But for the day-to-day work, SQL Source Control uses the same technique as SQL Compare to determine what changes have been made to your development database and how to represent those in your repository scripts.  I think that once I retrain myself to just work in the database and quit worrying about having to find and open the right script file, that this will actually make us more efficient. And for deployment purposes, SQL Source Control integrates with the full SQL Compare utility to produce a synchronization script (or do a live sync).  This is similar in concept to Microsoft’s DACPAC, if you’re familiar with that. If you are not currently keeping your database development efforts under source control, definitely examine this tool.  If you already have a methodology that is working for you, then I still think this is worth a review and comparison to your current approach.  You may find it more efficient.  But remember that the version which integrates with Vault/Fortress is still in pre-release mode, so treat it with a little caution.  I have found it to be fairly stable, but there was one bug that I found which had inconvenient side-effects and could have really been frustrating if I had been running this on my normal active development machine.  However, I can verify that that bug has been fixed in a more recent build version (did I mention Red-Gate’s responsiveness?).

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• What Counts For a DBA: Simplicity

  - by Louis Davidson

  Too many computer processes do an apparently simple task in a bizarrely complex way. They remind me of this strip by one of my favorite artists: Rube Goldberg. In order to keep the boss from knowing one was late, a process is devised whereby the cuckoo clock kisses a live cuckoo bird, who then pulls a string, which triggers a hat flinging, which in turn lands on a rod that removes a typewriter cover…and so on. We rely on creating automated processes to keep on top of tasks. DBAs have a lot of tasks to perform: backups, performance tuning, data movement, system monitoring, and of course, avoiding being noticed.  Every day, there are many steps to perform to maintain the database infrastructure, including: checking physical structures, re-indexing tables where needed, backing up the databases, checking those backups, running the ETL, and preparing the daily reports and yes, all of these processes have to complete before you can call it a day, and probably before many others have started that same day. Some of these tasks are just naturally complicated on their own. Other tasks become complicated because the database architecture is excessively rigid, and we often discover during “production testing” that certain processes need to be changed because the written requirements barely resembled the actual customer requirements.   Then, with no time to change that rigid structure, we are forced to heap layer upon layer of code onto the problematic processes. Instead of a slight table change and a new index, we end up with 4 new ETL processes, 20 temp tables, 30 extra queries, and 1000 lines of SQL code.  Report writers then need to build reports and make magical numbers appear from those toxic data structures that are overly complex and probably filled with inconsistent data. What starts out as a collection of fairly simple tasks turns into a Goldbergian nightmare of daily processes that are likely to cause your dinner to be interrupted by the smartphone doing the vibration dance that signifies trouble at the mill. So what to do? Well, if it is at all possible, simplify the problem by either going into the code and refactoring the complex code to simple, or taking all of the processes and simplifying them into small, independent, easily-tested steps.  The former approach usually requires an agreement on changing underlying structures that requires countless mind-numbing meetings; while the latter can generally be done to any complex process without the same frustration or anger, though it will still leave you with lots of steps to complete, the ability to test each step independently will definitely increase the quality of the overall process (and with each step reporting status back, finding an actual problem within the process will be definitely less unpleasant.) We all know the principle behind simplifying a sequence of processes because we learned it in math classes in our early years of attending school, starting with elementary school. In my 4 years (ok, 9 years) of undergraduate work, I remember pretty much one thing from my many math classes that I apply daily to my career as a data architect, data programmer, and as an occasional indentured DBA: “show your work”. This process of showing your work was my first lesson in simplification. Each step in the process was in fact, far simpler than the entire process.  When you were working an equation that took both sides of 4 sheets of paper, showing your work was important because the teacher could see every step, judge it, and mark it accordingly.  So often I would make an error in the first few lines of a problem which meant that the rest of the work was actually moving me closer to a very wrong answer, no matter how correct the math was in the subsequent steps. Yet, when I got my grade back, I would sometimes be pleasantly surprised. I passed, yet missed every problem on the test. But why? While I got the fact that 1+1=2 wrong in every problem, the teacher could see that I was using the right process. In a computer process, the process is very similar. We take complex processes, show our work by storing intermediate values, and test each step independently. When a process has 100 steps, each step becomes a simple step that is tested and verified, such that there will be 100 places where data is stored, validated, and can be checked off as complete. If you get step 1 of 100 wrong, you can fix it and be confident (that if you did your job of testing the other steps better than the one you had to repair,) that the rest of the process works. If you have 100 steps, and store the state of the process exactly once, the resulting testable chunk of code will be far more complex and finding the error will require checking all 100 steps as one, and usually it would be easier to find a specific needle in a stack of similarly shaped needles.  The goal is to strive for simplicity either in the solution, or at least by simplifying every process down to as many, independent, testable, simple tasks as possible.  For the tasks that really can’t be done completely independently, minimally take those tasks and break them down into simpler steps that can be tested independently.  Like working out division problems longhand, have each step of the larger problem verified and tested.

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• How do I prove or disprove "god" objects are wrong?

  - by honestduane

  Problem Summary: Long story short, I inherited a code base and an development team I am not allowed to replace and the use of God Objects is a big issue. Going forward, I want to have us re-factor things but I am getting push-back from the teams who want to do everything with God Objects "because its easier" and this means I would not be allowed to re-factor. I pushed back citing my years of dev experience, that I'm the new boss who was hired to know these things, etc, and so did the third party offshore companies account sales rep, and this is now at the executive level and my meeting is tomorrow and I want to go in with a lot of technical ammo to advocate best practices because I feel it will be cheaper in the long run (And I personally feel that is what the third party is worried about) for the company. My issue is from a technical level, I know its good long term but I'm having trouble with the ultra short term and 6 months term, and while its something I "know" I cant prove it with references and cited resources outside of one person (Robert C. Martin, aka Uncle Bob), as that is what I am being asked to do as I have been told having data from one person and only one person (Robert C Martin) is not good enough of an argument. Question: What are some resources I can cite directly (Title, year published, page number, quote) by well known experts in the field that explicitly say this use of "God" Objects/Classes/Systems is bad (or good, since we are looking for the most technically valid solution)? Research I have already done: I have a number of books here and I have searched their indexes for the use of the words "god object" and "god class". I found that oddly its almost never used and the copy of the GoF book I have for example, never uses it (At least according to the index in front of me) but I have found it in 2 books per the below, but I want more I can use. I checked the Wikipedia page for "God Object" and its currently a stub with little reference links so although I personally agree with that it says, It doesn't have much I can use in an environment where personal experience is not considered valid. The book cited is also considered too old to be valid by the people I am debating these technical points with as the argument they are making is that "it was once thought to be bad but nobody could prove it, and now modern software says "god" objects are good to use". I personally believe that this statement is incorrect, but I want to prove the truth, whatever it is. In Robert C Martin's "Agile Principles, Patterns, and Practices in C#" (ISBN: 0-13-185725-8, hardcover) where on page 266 it states "Everybody knows that god classes are a bad idea. We don't want to concentrate all the intelligence of a system into a single object or a single function. One of the goals of OOD is the partitioning and distribution of behavior into many classes and many function." -- And then goes on to say sometimes its better to use God Classes anyway sometimes (Citing micro-controllers as an example). In Robert C Martin's "Clean Code: A Handbook of Agile Software Craftsmanship" page 136 (And only this page) talks about the "God class" and calls it out as a prime example of a violation of the "classes should be small" rule he uses to promote the Single Responsibility Principle" starting on on page 138. The problem I have is all my references and citations come from the same person (Robert C. Martin), and am from the same single person/source. I am being told that because he is just one guy, my desire to not use "God Classes" is invalid and not accepted as a standard best practice in the software industry. Is this true? Am I doing things wrong from a technical perspective by trying to keep to the teaching of Uncle Bob? God Objects and Object Oriented Programming and Design: The more I think of this the more I think this is more something you learn when you study OOP and its never explicitly called out; Its implicit to good design is my thinking (Feel free to correct me, please, as I want to learn), The problem is I "know" this, but but not everybody does, so in this case its not considered a valid argument because I am effectively calling it out as universal truth when in fact most people are statistically ignorant of it since statistically most people are not programmers. Conclusion: I am at a loss on what to search for to get the best additional results to cite, since they are making a technical claim and I want to know the truth and be able to prove it with citations like a real engineer/scientist, even if I am biased against god objects due to my personal experience with code that used them. Any assistance or citations would be deeply appreciated.

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• Subscribable World Cup 2010 Calendar

  - by jamiet

  I bang on quite a lot on this blog about ways in which data can get published over the web and one of the most interesting ways, in my opinion, of publishing data in a structured manner that is well understood is to use the iCalendar specification. There isn’t much information in the world that doesn’t have some concept of “when” so iCalendar is a great way of distributing that information. You have probably used iCalendar at some point without even knowing about it. All files with a .ics suffix are iCalendar format files and that is why you can happily import them into Outlook, Hotmail Calendar, Google Calendar etc… where they can be parsed and have the semantic data (when, where and who) extracted from them. Importing of iCalendar format data is really only half the trick though; in my opinion the real value of iCalendar-formatted calendar is the ability to subscribe to them. Subscribing has a simple benefit over importing but that single benefit is of massive importance: a subscriber to an iCalendar calendar can periodically check to see if any updates have been made and, if they have, automatically update the local copy. The real benefit to the user is the productivity gain – a single update to an iCalendar means that all subscribers are automatically made aware of the change and there is zero effort on the part of the subscriber; as my former colleague Howard van Rooijen is fond of saying, “work smarter not harder” – nowhere is this edict more ably demonstrated than subscribing versus importing of calendars. If you want to read some more thoughts about iCalendar then go and read my past blog post Calendar syndication - My big hope for 2009's breakthrough technology or better still go and seek out Jon Udell who speaks very authoritatively on the issue of iCalendar. With this subject of iCalendar on my mind I was interested to discover (via Steve Clayton’s blog post Download the world cup fixtures) that the BBC had made a .ics file available containing all of the matches in the upcoming World Cup. As you can probably guess this was a file that was made available so that it could be imported into your calendar of choice. It had one obvious downside though, right now nobody knows who is going to be playing in the knock-out stages so the calendar looks like this: with no teams being named after 25th June. How much more useful would this calendar have been if the BBC had made it possible to subscribe to the calendar instead, thus the calendar could be updated with the teams for the knock out stages when they are known and every subscriber would have a permanently up-to-date record of all the fixtures in their calendar. Better still, the calendar could be updated with match results as well or perhaps even post a match report from the BBC sport pages; when calendars are made subscribable a sea of opportunity opens up for distribution of information. So with that in mind I have decided to go one better than the BBC. I have imported their .ics into a brand new Hotmail calendar and made it publicly available at the following URLs: HTML http://cid-dc1ed121af0476be.calendar.live.com/calendar/World+Cup+2010/index.html iCalendar webcal://cid-dc1ed121af0476be.calendar.live.com/calendar/World+Cup+2010/calendar.ics The link you’re really interested in is the second one - click on that and it should open up in your calendar software of choice. Or, if you want to view it in an online calendar such as Hotmail Calendar or Google Calendar, copy and paste that URL into the appropriate place. Some people have told me they’re having trouble with the iCalendar link in which case hit the HTML link and then click “View ICS” at the resultant web page: I shall endeavour to keep the calendar updated throughout the World Cup and even if I don’t you’re no worse off than if you had imported the BBC’s .ics file so why not give it a try? If I do keep it up to date then you will have a permanent record of the 2010 World Cup available in your calendar. Forever. If you have your calendar synced to your smartphone then you’ll be carrying match reports around with you without you having to do a single thing. Surely that’s worth a quick click isn’t it?   If you have any thoughts let me have them in the comments below. Thanks for reading. @Jamiet Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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• using isight camera in macbookpro(8,2) on ubuntu 12.04 virtualbox VM

  - by Kurt Spindler

  I'm having a lot of trouble using the built-in isight camera on my macbookpro8,2 (early 2011) from an ubuntu 12.04 virtual machine, run inside VirtualBox. The following is the log I get when I try to run guvcview ubuntu@ubuntu:~$ guvcview guvcview 1.5.3 ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.rear ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.center_lfe ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.side ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.surround71 ALSA lib setup.c:565:(add_elem) Cannot obtain info for CTL elem (MIXER,'IEC958 Playback Default',0,0,0): No such file or directory ALSA lib setup.c:565:(add_elem) Cannot obtain info for CTL elem (MIXER,'IEC958 Playback Default',0,0,0): No such file or directory ALSA lib setup.c:565:(add_elem) Cannot obtain info for CTL elem (MIXER,'IEC958 Playback Default',0,0,0): No such file or directory ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.hdmi ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.hdmi ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.modem ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.modem ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.phoneline ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.phoneline ALSA lib audio/pcm_bluetooth.c:1614:(audioservice_expect) BT_GET_CAPABILITIES failed : Input/output error(5) ALSA lib audio/pcm_bluetooth.c:1614:(audioservice_expect) BT_GET_CAPABILITIES failed : Input/output error(5) ALSA lib audio/pcm_bluetooth.c:1614:(audioservice_expect) BT_GET_CAPABILITIES failed : Input/output error(5) ALSA lib audio/pcm_bluetooth.c:1614:(audioservice_expect) BT_GET_CAPABILITIES failed : Input/output error(5) ALSA lib pcm_dmix.c:957:(snd_pcm_dmix_open) The dmix plugin supports only playback stream Cannot connect to server socket err = No such file or directory Cannot connect to server socket jack server is not running or cannot be started video device: /dev/video0 Init. FaceTime HD Camera (Built-in) (location: usb-0000:00:0b.0-1) { pixelformat = 'YUYV', description = 'YUV 4:2:2 (YUYV)' } { discrete: width = 160, height = 120 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 176, height = 144 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 320, height = 240 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 352, height = 288 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 640, height = 480 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1280, height = 720 } Time interval between frame: 1/10, { pixelformat = 'MJPG', description = 'MJPEG' } { discrete: width = 960, height = 540 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1024, height = 576 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1280, height = 720 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { pixelformat = 'RGB3', description = 'RGB3' } { discrete: width = 160, height = 120 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 176, height = 144 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 320, height = 240 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 352, height = 288 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 640, height = 480 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1280, height = 720 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 960, height = 540 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1024, height = 576 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { pixelformat = 'BGR3', description = 'BGR3' } { discrete: width = 160, height = 120 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 176, height = 144 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 320, height = 240 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 352, height = 288 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 640, height = 480 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1280, height = 720 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 960, height = 540 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1024, height = 576 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { pixelformat = 'YU12', description = 'YU12' } { discrete: width = 160, height = 120 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 176, height = 144 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 320, height = 240 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 352, height = 288 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 640, height = 480 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1280, height = 720 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 960, height = 540 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1024, height = 576 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { pixelformat = 'YV12', description = 'YV12' } { discrete: width = 160, height = 120 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 176, height = 144 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 320, height = 240 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 352, height = 288 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 640, height = 480 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1280, height = 720 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 960, height = 540 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1024, height = 576 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, vid:05ac pid:8509 driver:uvcvideo checking format: 1196444237 VIDIOC_G_COMP:: Invalid argument compression control not supported fps is set to 1/25 drawing controls no codec detected for H264 no codec detected for MP3 - (lavc) Checking video mode 960x540@32bpp : OK Could not grab image (select timeout): Resource temporarily unavailable Could not grab image (select timeout): Resource temporarily unavailable Could not grab image (select timeout): Resource temporarily unavailable Could not grab image (select timeout): Resource temporarily unavailable Could not grab image (select timeout): Resource temporarily unavailable Could not grab image (select timeout): Resource temporarily unavailable Could not grab image (select timeout): Resource temporarily unavailable Could not grab image (select timeout): Resource temporarily unavailable Could not grab image (select timeout): Resource temporarily unavailable write /home/ubuntu/.guvcviewrc OK free controls cleaned allocations - 100% Closing portaudio ...OK Closing GTK... OK ubuntu@ubuntu:~$ Any help would be greatly appreciated. Only clue I have is that I initially was having problems, tried using the old method of fixing isights (involving installing isight-firmware-tools) before realizing that I just hadn't turned on the VM setting to allow the VM to access the webcam. :) Anyway, I wonder if installing that messed something up. However, I think this is a red herring because I've: shut down and turned back on the Mac, restarted the VM, tried a different VM (for which I never installed isight-firmware-tools, and created an entirely new ubuntu vm. All instances have had this problem. Similarly, other viewers, such as cheese, avplay, avconv have had all various kinds of errors.

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• Tuning Red Gate: #2 of Many

  - by Grant Fritchey

  In the last installment, I used the SQL Monitor tool to get a snapshot view of the current state of the servers at Red Gate that are giving us trouble. That snapshot suggested some areas where I should focus some time, primarily in which queries were being called most frequently or were running the longest. But, you don't want to just run off & start tuning queries. Remember, the foundation for query tuning is the server itself. So, I want to be sure I'm not looking at some major hardware or configuration issues that I need to address first. Rather than look at the current status of the server, I'm going to look at historical data. Clicking on the Analysis tab of SQL Monitor I get a whole list of counters that I can look at. More importantly, I can look at them over a period of time. Even more importantly, I can compare past periods with current periods to see if we're looking at a progressive issue or not. There are counters here that will give me an indication of load, and there are counters here that will tell me specifics about that load. First, I want to just look at the load to understand where the pain points might be. Trying to drill down before you have detailed information is just bad planning. First thing I'm going to check is the CPU, just to see what's up there. I have two servers I'm interested in, so I'll show you both: Looking at the last 30 days for both servers, well, let's just say that the first server is about what I would expect. It has an average baseline behavior with occasional, regular, peaks. This looks like a system with a fairly steady & predictable load that probably has a nightly batch process that spikes the processor. In short, normal stuff. The points there where the CPU drops radically. that might be worth investigating further because something changed the processing on this system a lot. But the first server. It's all over the place. There's no steady CPU behavior at all. It's spike high for long periods of time. It's up, it's down. I'm really going to have to spend time looking at CPU issues on this server to try to figure out what's up. It might be other processes being shared on the server, it might be something else. Either way, I'm going to have to spend time evaluating this CPU, especially those peeks about a week ago. Looking at the Pages/sec, again, just a measure of load, I see that there are some peaks on the rg-sql02 server, but over all, it looks like a fairly standard load. Plus, the peaks are only up to 550 pages/sec. Remember, this isn't a performance measure, but just a load measurement, but from this, I don't think we're looking at major memory issues, but I may want to correlate these counters with the CPU counters. Again, the other server looks like there's stuff going on. The load is not at all consistent. In fact there was a point earlier in the year that looks pretty severe. Plus the spikes here are twice the size of the other system. We've got a lot more load going on here and I will probably need to drill down on memory usage on this server. Taking a look at the disk transfers/sec the load on both systems seems to roughly correspond to the other load indicators. Notice that drop right in the middle of the graph for rg-sql02. I wonder if the office was closed over that period or a system was down for maintenance. If I saw spikes in memory or disk that corresponded to the drip in CPU, you can assume something was using those other resources and causing a drop, but when everything goes down, it just means that the system isn't gettting used. The disk on the rg-sql01 system isn't spiking exactly the same way as the memory & cpu, so there's a good chance (chance mind you) that any performance issues might not be disk related. However, notice that huge jump at the beginning of the month. Several disks were used more than they were for the rest of the month. That's the load on the server. What about the load on SQL Server itself? Next time.

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• Cant get lm-sensors to load ATI Radeon temp and fan or output all settings

  - by woody

  New to Linux and having minor issues :/ . I followed this guide initially but did not recieve the proper output and did not show my ATI Radeon HD 5000 temp or fan speed. Then used this guide, same problems exhibited. No issues installing and no errors. I think its not reading i2c for some reason. The proprietary driver is installed and functioning correctly according fglrxinfo. I can use aticonfig commands and view both temp and fan. Any ideas on how to get the ATI Radeon sensors working under 'sensors'? When i run 'sudo sensors-detect' this is my ouput # sensors-detect revision 5984 (2011-07-10 21:22:53 +0200) # System: LENOVO IdeaPad Y560 (laptop) # Board: Lenovo KL3 This program will help you determine which kernel modules you need to load to use lm_sensors most effectively. It is generally safe and recommended to accept the default answers to all questions, unless you know what you're doing. Some south bridges, CPUs or memory controllers contain embedded sensors. Do you want to scan for them? This is totally safe. (YES/no): y Silicon Integrated Systems SIS5595... No VIA VT82C686 Integrated Sensors... No VIA VT8231 Integrated Sensors... No AMD K8 thermal sensors... No AMD Family 10h thermal sensors... No AMD Family 11h thermal sensors... No AMD Family 12h and 14h thermal sensors... No AMD Family 15h thermal sensors... No AMD Family 15h power sensors... No Intel digital thermal sensor... Success! (driver `coretemp') Intel AMB FB-DIMM thermal sensor... No VIA C7 thermal sensor... No VIA Nano thermal sensor... No Some Super I/O chips contain embedded sensors. We have to write to standard I/O ports to probe them. This is usually safe. Do you want to scan for Super I/O sensors? (YES/no): y Probing for Super-I/O at 0x2e/0x2f Trying family `National Semiconductor/ITE'... Yes Found unknown chip with ID 0x8502 Probing for Super-I/O at 0x4e/0x4f Trying family `National Semiconductor/ITE'... No Trying family `SMSC'... No Trying family `VIA/Winbond/Nuvoton/Fintek'... No Trying family `ITE'... No Some hardware monitoring chips are accessible through the ISA I/O ports. We have to write to arbitrary I/O ports to probe them. This is usually safe though. Yes, you do have ISA I/O ports even if you do not have any ISA slots! Do you want to scan the ISA I/O ports? (YES/no): y Probing for `National Semiconductor LM78' at 0x290... No Probing for `National Semiconductor LM79' at 0x290... No Probing for `Winbond W83781D' at 0x290... No Probing for `Winbond W83782D' at 0x290... No Lastly, we can probe the I2C/SMBus adapters for connected hardware monitoring devices. This is the most risky part, and while it works reasonably well on most systems, it has been reported to cause trouble on some systems. Do you want to probe the I2C/SMBus adapters now? (YES/no): y Using driver `i2c-i801' for device 0000:00:1f.3: Intel 3400/5 Series (PCH) Now follows a summary of the probes I have just done. Just press ENTER to continue: Driver `coretemp': * Chip `Intel digital thermal sensor' (confidence: 9) To load everything that is needed, add this to /etc/modules: #----cut here---- # Chip drivers coretemp #----cut here---- If you have some drivers built into your kernel, the list above will contain too many modules. Skip the appropriate ones! Do you want to add these lines automatically to /etc/modules? (yes/NO) My output for 'sensors' is: acpitz-virtual-0 Adapter: Virtual device temp1: +58.0°C (crit = +100.0°C) coretemp-isa-0000 Adapter: ISA adapter Core 0: +56.0°C (high = +84.0°C, crit = +100.0°C) Core 1: +57.0°C (high = +84.0°C, crit = +100.0°C) Core 2: +58.0°C (high = +84.0°C, crit = +100.0°C) Core 3: +57.0°C (high = +84.0°C, crit = +100.0°C) and my '/etc/modules' is: # /etc/modules: kernel modules to load at boot time. # # This file contains the names of kernel modules that should be loaded # at boot time, one per line. Lines beginning with "#" are ignored. lp rtc # Generated by sensors-detect on Fri Nov 30 23:24:31 2012 # Chip drivers coretemp

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• SQL SERVER – Recover the Accidentally Renamed Table

  - by pinaldave

  I have no answer to following question. I saw a desperate email marked as urgent delivered in my mailbox. “I accidentally renamed table in my SSMS. I was scrolling very fast and I made mistakes. It was either because I double clicked or clicked on F2 (shortcut key for renaming). However, I have made the mistake and now I have no idea how to fix this. I am in big trouble. Help me get my original tablename.” I have seen many similar scenarios in my life and they give me a very good opportunity to preach wisdom but when the house is burning, we cannot talk about how we should have conserved the water earlier. The goal at that point is to put off the fire as fast as we can. I decided to answer this email with my best knowledge. If you have renamed the table, I think you pretty much is out of luck. Here are few things which you can do which can give you idea about what your tablename can be if you are lucky. Method 1: (Not Recommended but try your luck) Check your naming convention of your system. I have often seen that many organizations name their index as IX_TableName_Colms or name their keys as FK_TableName1_TableName2_Cols. If your organization is following the same you can get the name from your table, you may refer your keys. Again, note that this is quite possible that your tablename was already renamed and your keys were not updated. This can easily lead you to select incorrect name. I think follow this if you are confident or move to the next method. Method 2: (Not Recommended but try your luck) This method is also based on your orgs naming convention. If you use the name of the table in any columnname (some organizations use tablename in their incremental identity column name), you can get that name from there. Method 3: (Not Recommended but try your luck) If you know where your table was used in your stored procedures, you can script your stored procedure and find the name of the table back. Method 4: (Try your luck) All the best organizations first create a data model of the schema and there is good chance that this table is used there, you should take your chances and refer original document. If your organization is good at managing docs or source code, you will get the name of the table back for sure. Method 5: (It WORKS but try on a development server) There is no sure way to get you the name of the table which you accidentally renamed however, there is one way which will work for sure. You need to take your latest full backup and restore it on your development server (remember not on production or where you have renamed this column). Now restore latest differential file of the full backup. Now restore all the log files one by one making sure that you are restoring before the point of time of you renamed the tablename. Now go to explore and this will give you the name of the table which you have renamed. If you are confident that the same table existed with the same name when the last full backup was made, you do not have to go to all the steps. You can just get the name of the table directly from last backup’s restore. Read the article about Backup Timeline. Wisdom: How can I miss to preach wisdom when I get the opportunity to do so? Here are a few points to remember. Use a different account to explore production environment. Do not use the same account which have all the rights and permissions all the time. Use the account which has read only permissions if there are no modification required. Use policy based management to prevent changes which are accidental. If there was policy of valid names, the accidental change of the table was not possible unless it was intentional delibarate changes. Have a proper auditing of the system in place. You can use DDL triggers but be careful with its usage (get it reviewed properly first). (Add your suggestion here) I guess Method 5 will work all the time (using point in time restore). Everything else is chance of luck and if you are lucky are bad – you will get further incorrect name. Now go back and read the first line of this blog. Out of five method four methods are just lucky guesses. The method 5 will work but again it is a lengthy process if the size of the database is huge or if you do not have full backup. Did I miss anything obvious? Please leave a comment and I will publish your answer with due credit. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Puzzle, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Simple Project Templates

  - by Geertjan

  The NetBeans sources include a module named "simple.project.templates": In the module sources, Tim Boudreau turns out to be the author of the code, so I asked him what it was all about, and if he could provide some usage code. His response, from approximately this time last year because it's been sitting in my inbox for a while, is below. Sure - though I think the javadoc in it is fairly complete.  I wrote it because I needed to create a bunch of project templates for Javacard, and all of the ways that is usually done were grotesque and complicated.  I figured we already have the ability to create files from templates, and we already have the ability to do substitutions in templates, so why not have a single file that defines the project as a list of file templates to create (with substitutions in the names) and some definitions of what should be in project properties. You can also add files to the project programmatically if you want.Basically, a template for an entire project is a .properties file.  Any line which doesn't have the prefix 'pp.' or 'pvp.' is treated as the definition of one file which should be created in the new project.  Any such line where the key ends in * means that file should be opened once the new project is created.  So, for example, in the nodejs module, the definition looks like: {{projectName}}.js*=Templates/javascript/HelloWorld.js .npmignore=node_hidden_templates/npmignore So, the first line means:  - Create a file with the same name as the project, using the HelloWorld template    - I.e. the left side of the line is the relative path of the file to create, and the right side is the path in the system filesystem for the template to use       - If the template is not one you normally want users to see, just register it in the system filesystem somewhere other than Templates/ (but remember to set the attribute that marks it as a template)  - Include that file in the set of files which should be opened in the editor once the new project is created. To actually create a project, first you just create a new ProjectCreator: ProjectCreator gen = new ProjectCreator( parentFolderOfNewProject ); Now, if you want to programmatically generate any files, in addition to those defined in the template, you can: gen.add (new FileCreator("nbproject", "project.xml", false) {     public DataObject create (FileObject project, Map<String,String> substitutions) throws IOException {          ...     } }); Then pass the FileObject for the project template (the properties file) to the ProjectCreator's createProject method (hmm, maybe it should be the string path to the project template instead, to save the caller trouble looking up the FileObject for the template).  That method looks like this: public final GeneratedProject createProject(final ProgressHandle handle, final String name, final FileObject template, final Map<String, String> substitutions) throws IOException { The name parameter should be the directory name for the new project;  the map is the strings you gathered in the wizard which should be used for substitutions.  createProject should be called on a background thread (i.e. use a ProgressInstantiatingIterator for the wizard iterator and just pass in the ProgressHandle you are given). The return value is a GeneratedProject object, which is just a holder for the created project directory and the set of DataObjects which should be opened when the wizard finishes. I'd love to see simple.project.templates moved out of the javacard cluster, as it is really useful and much simpler than any of the stuff currently done for generating projects.  It would also be possible to do much richer tools for creating projects in apisupport - i.e. choose (or create in the wizard) the templates you want to use, generate a skeleton wizard with a UI for all the properties you'd like to substitute, etc. Here is a partial project template from Javacard - for example usage, see org.netbeans.modules.javacard.wizard.ProjectWizardIterator in javacard.project (or the much simpler one in contrib/nodejs). #This properties file describes what to create when a project template is#instantiated.  The keys are paths on disk relative to the project root. #The values are paths to the templates to use for those files in the system#filesystem.  Any string inside {{ and }}'s will be substituted using properties#gathered in the template wizard.#Special key prefixes are #  pp. - indicates an entry for nbproject/project.properties#  pvp. - indicates an entry for nbproject/private/private.properties #File templates, in format [path-in-project=path-to-template]META-INF/javacard.xml=org-netbeans-modules-javacard/templates/javacard.xmlMETA-INF/MANIFEST.MF=org-netbeans-modules-javacard/templates/EAP_MANIFEST.MF APPLET-INF/applet.xml=org-netbeans-modules-javacard/templates/applet.xmlscripts/{{classnamelowercase}}.scr=org-netbeans-modules-javacard/templates/test.scrsrc/{{packagepath}}/{{classname}}.java*=Templates/javacard/ExtendedApplet.java nbproject/deployment.xml=org-netbeans-modules-javacard/templates/deployment.xml#project.properties contentspp.display.name={{projectname}}pp.platform.active={{activeplatform}} pp.active.device={{activedevice}}pp.includes=**pp.excludes= I will be using the above info in an upcoming blog entry and provide step by step instructions showing how to use them. However, anyone else out there should have enough info from the above to get started yourself!

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• How to Tell If Your Computer is Overheating and What to Do About It

  - by Chris Hoffman

  Heat is a computer’s enemy. Computers are designed with heat dispersion and ventilation in mind so they don’t overheat. If too much heat builds up, your computer may become unstable or suddenly shut down. The CPU and graphics card produce much more heat when running demanding applications. If there’s a problem with your computer’s cooling system, an excess of heat could even physically damage its components. Is Your Computer Overheating? When using a typical computer in a typical way, you shouldn’t have to worry about overheating at all. However, if you’re encountering system instability issues like abrupt shut downs, blue screens, and freezes — especially while doing something demanding like playing PC games or encoding video — your computer may be overheating. This can happen for several reasons. Your computer’s case may be full of dust, a fan may have failed, something may be blocking your computer’s vents, or you may have a compact laptop that was never designed to run at maximum performance for hours on end. Monitoring Your Computer’s Temperature First, bear in mind that different CPUs and GPUs (graphics cards) have different optimal temperature ranges. Before getting too worried about a temperature, be sure to check your computer’s documentation — or its CPU or graphics card specifications — and ensure you know the temperature ranges your hardware can handle. You can monitor your computer’s temperatures in a variety of different ways. First, you may have a way to monitor temperature that is already built into your system. You can often view temperature values in your computer’s BIOS or UEFI settings screen. This allows you to quickly see your computer’s temperature if Windows freezes or blue screens on you — just boot the computer, enter the BIOS or UEFI screen, and check the temperatures displayed there. Note that not all BIOSes or UEFI screens will display this information, but it is very common. There are also programs that will display your computer’s temperature. Such programs just read the sensors inside your computer and show you the temperature value they report, so there are a wide variety of tools you can use for this, from the simple Speccy system information utility to an advanced tool like SpeedFan. HWMonitor also offer this feature, displaying a wide variety of sensor information. Be sure to look at your CPU and graphics card temperatures. You can also find other temperatures, such as the temperature of your hard drive, but these components will generally only overheat if it becomes extremely hot in the computer’s case. They shouldn’t generate too much heat on their own. If you think your computer may be overheating, don’t just glance as these sensors once and ignore them. Do something demanding with your computer, such as running a CPU burn-in test with Prime 95, playing a PC game, or running a graphical benchmark. Monitor the computer’s temperature while you do this, even checking a few hours later — does any component overheat after you push it hard for a while? Preventing Your Computer From Overheating If your computer is overheating, here are some things you can do about it: Dust Out Your Computer’s Case: Dust accumulates in desktop PC cases and even laptops over time, clogging fans and blocking air flow. This dust can cause ventilation problems, trapping heat and preventing your PC from cooling itself properly. Be sure to clean your computer’s case occasionally to prevent dust build-up. Unfortunately, it’s often more difficult to dust out overheating laptops. Ensure Proper Ventilation: Put the computer in a location where it can properly ventilate itself. If it’s a desktop, don’t push the case up against a wall so that the computer’s vents become blocked or leave it near a radiator or heating vent. If it’s a laptop, be careful to not block its air vents, particularly when doing something demanding. For example, putting a laptop down on a mattress, allowing it to sink in, and leaving it there can lead to overheating — especially if the laptop is doing something demanding and generating heat it can’t get rid of. Check if Fans Are Running: If you’re not sure why your computer started overheating, open its case and check that all the fans are running. It’s possible that a CPU, graphics card, or case fan failed or became unplugged, reducing air flow. Tune Up Heat Sinks: If your CPU is overheating, its heat sink may not be seated correctly or its thermal paste may be old. You may need to remove the heat sink and re-apply new thermal paste before reseating the heat sink properly. This tip applies more to tweakers, overclockers, and people who build their own PCs, especially if they may have made a mistake when originally applying the thermal paste. This is often much more difficult when it comes to laptops, which generally aren’t designed to be user-serviceable. That can lead to trouble if the laptop becomes filled with dust and needs to be cleaned out, especially if the laptop was never designed to be opened by users at all. Consult our guide to diagnosing and fixing an overheating laptop for help with cooling down a hot laptop. Overheating is a definite danger when overclocking your CPU or graphics card. Overclocking will cause your components to run hotter, and the additional heat will cause problems unless you can properly cool your components. If you’ve overclocked your hardware and it has started to overheat — well, throttle back the overclock! Image Credit: Vinni Malek on Flickr     

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• Clean way to use mutable implementation of Immutable interfaces for encapsulation

  - by dsollen

  My code is working on some compost relationship which creates a tree structure, class A has many children of type B, which has many children of type C etc. The lowest level class, call it bar, also points to a connected bar class. This effectively makes nearly every object in my domain inter-connected. Immutable objects would be problematic due to the expense of rebuilding almost all of my domain to make a single change to one class. I chose to go with an interface approach. Every object has an Immutable interface which only publishes the getter methods. I have controller objects which constructs the domain objects and thus has reference to the full objects, thus capable of calling the setter methods; but only ever publishes the immutable interface. Any change requested will go through the controller. So something like this: public interface ImmutableFoo{ public Bar getBar(); public Location getLocation(); } public class Foo implements ImmutableFoo{ private Bar bar; private Location location; @Override public Bar getBar(){ return Bar; } public void setBar(Bar bar){ this.bar=bar; } @Override public Location getLocation(){ return Location; } } public class Controller{ Private Map<Location, Foo> fooMap; public ImmutableFoo addBar(Bar bar){ Foo foo=fooMap.get(bar.getLocation()); if(foo!=null) foo.addBar(bar); return foo; } } I felt the basic approach seems sensible, however, when I speak to others they always seem to have trouble envisioning what I'm describing, which leaves me concerned that I may have a larger design issue then I'm aware of. Is it problematic to have domain objects so tightly coupled, or to use the quasi-mutable approach to modifying them? Assuming that the design approach itself isn't inherently flawed the particular discussion which left me wondering about my approach had to do with the presence of business logic in the domain objects. Currently I have my setter methods in the mutable objects do error checking and all other logic required to verify and make a change to the object. It was suggested that this should be pulled out into a service class, which applies all the business logic, to simplify my domain objects. I understand the advantage in mocking/testing and general separation of logic into two classes. However, with a service method/object It seems I loose some of the advantage of polymorphism, I can't override a base class to add in new error checking or business logic. It seems, if my polymorphic classes were complicated enough, I would end up with a service method that has to check a dozen flags to decide what error checking and business logic applies. So, for example, if I wanted to have a childFoo which also had a size field which should be compared to bar before adding par my current approach would look something like this. public class Foo implements ImmutableFoo{ public void addBar(Bar bar){ if(!getLocation().equals(bar.getLocation()) throw new LocationException(); this.bar=bar; } } public interface ImmutableChildFoo extends ImmutableFoo{ public int getSize(); } public ChildFoo extends Foo implements ImmutableChildFoo{ private int size; @Override public int getSize(){ return size; } @Override public void addBar(Bar bar){ if(getSize()<bar.getSize()){ throw new LocationException(); super.addBar(bar); } My colleague was suggesting instead having a service object that looks something like this (over simplified, the 'service' object would likely be more complex). public interface ImmutableFoo{ ///original interface, presumably used in other methods public Location getLocation(); public boolean isChildFoo(); } public interface ImmutableSizedFoo implements ImmutableFoo{ public int getSize(); } public class Foo implements ImmutableSizedFoo{ public Bar bar; @Override public void addBar(Bar bar){ this.bar=bar; } @Override public int getSize(){ //default size if no size is known return 0; } @Override public boolean isChildFoo return false; } } public ChildFoo extends Foo{ private int size; @Override public int getSize(){ return size; } @Override public boolean isChildFoo(); return true; } } public class Controller{ Private Map<Location, Foo> fooMap; public ImmutableSizedFoo addBar(Bar bar){ Foo foo=fooMap.get(bar.getLocation()); service.addBarToFoo(foo, bar); returned foo; } public class Service{ public static void addBarToFoo(Foo foo, Bar bar){ if(foo==null) return; if(!foo.getLocation().equals(bar.getLocation())) throw new LocationException(); if(foo.isChildFoo() && foo.getSize()<bar.getSize()) throw new LocationException(); foo.setBar(bar); } } } Is the recommended approach of using services and inversion of control inherently superior, or superior in certain cases, to overriding methods directly? If so is there a good way to go with the service approach while not loosing the power of polymorphism to override some of the behavior?

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• SQL SERVER – Curious Case of Disappearing Rows – ON UPDATE CASCADE and ON DELETE CASCADE – Part 1 of 2

  - by pinaldave

  Social media has created an Always Connected World for us. Recently I enrolled myself to learn new technologies as a student. I had decided to focus on learning and decided not to stay connected on the internet while I am in the learning session. On the second day of the event after the learning was over, I noticed lots of notification from my friend on my various social media handle. He had connected with me on Twitter, Facebook, Google+, LinkedIn, YouTube as well SMS, WhatsApp on the phone, Skype messages and not to forget with a few emails. I right away called him up. The problem was very unique – let us hear the problem in his own words. “Pinal – we are in big trouble we are not able to figure out what is going on. Our product details table is continuously loosing rows. Lots of rows have disappeared since morning and we are unable to find why the rows are getting deleted. We have made sure that there is no DELETE command executed on the table as well. The matter of the fact, we have removed every single place the code which is referencing the table. We have done so many crazy things out of desperation but no luck. The rows are continuously deleted in a random pattern. Do you think we have problems with intrusion or virus?” After describing the problems he had pasted few rants about why I was not available during the day. I think it will be not smart to post those exact words here (due to many reasons). Well, my immediate reaction was to get online with him. His problem was unique to him and his team was all out to fix the issue since morning. As he said he has done quite a lot out in desperation. I started asking questions from audit, policy management and profiling the data. Very soon I realize that I think this problem was not as advanced as it looked. There was no intrusion, SQL Injection or virus issue. Well, long story short first - It was a very simple issue of foreign key created with ON UPDATE CASCADE and ON DELETE CASCADE.  CASCADE allows deletions or updates of key values to cascade through the tables defined to have foreign key relationships that can be traced back to the table on which the modification is performed. ON DELETE CASCADE specifies that if an attempt is made to delete a row with a key referenced by foreign keys in existing rows in other tables, all rows containing those foreign keys are also deleted. ON UPDATE CASCADE specifies that if an attempt is made to update a key value in a row, where the key value is referenced by foreign keys in existing rows in other tables, all of the foreign key values are also updated to the new value specified for the key. (Reference: BOL) In simple words – due to ON DELETE CASCASE whenever is specified when the data from Table A is deleted and if it is referenced in another table using foreign key it will be deleted as well. In my friend’s case, they had two tables, Products and ProductDetails. They had created foreign key referential integrity of the product id between the table. Now the as fall was up they were updating their catalogue. When they were updating the catalogue they were deleting products which are no more available. As the changes were cascading the corresponding rows were also deleted from another table. This is CORRECT. The matter of the fact, there is no error or anything and SQL Server is behaving how it should be behaving. The problem was in the understanding and inappropriate implementations of business logic.  What they needed was Product Master Table, Current Product Catalogue, and Product Order Details History tables. However, they were using only two tables and without proper understanding the relation between them was build using foreign keys. If there were only two table, they should have used soft delete which will not actually delete the record but just hide it from the original product table. This workaround could have got them saved from cascading delete issues. I will be writing a detailed post on the design implications etc in my future post as in above three lines I cannot cover every issue related to designing and it is also not the scope of the blog post. More about designing in future blog posts. Once they learn their mistake, they were happy as there was no intrusion but trust me sometime we are our own enemy and this is a great example of it. In tomorrow’s blog post we will go over their code and workarounds. Feel free to share your opinions, experiences and comments. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• The Joy Of Hex

  - by Jim Giercyk

  While working on a mainframe integration project, it occurred to me that some basic computer concepts are slipping into obscurity. For example, just about anyone can tell you that a 64-bit processor is faster than a 32-bit processer. A grade school child could tell you that a computer “speaks” in ‘1’s and ‘0’s. Some people can even tell you that there are 8 bits in a byte. However, I have found that even the most seasoned developers often can’t explain the theory behind those statements. That is not a knock on programmers; in the age of IntelliSense, what reason do we have to work with data at the bit level? Many computer theory classes treat bit-level programming as a thing of the past, no longer necessary now that storage space is plentiful. The trouble with that mindset is that the world is full of legacy systems that run programs written in the 1970’s.  Today our jobs require us to extract data from those systems, regardless of the format, and that often involves low-level programming. Because it seems knowledge of the low-level concepts is waning in recent times, I thought a review would be in order.       CHARACTER: See Spot Run HEX: 53 65 65 20 53 70 6F 74 20 52 75 6E DECIMAL: 83 101 101 32 83 112 111 116 32 82 117 110 BINARY: 01010011 01100101 01100101 00100000 01010011 01110000 01101111 01110100 00100000 01010010 01110101 01101110 In this example, I have broken down the words “See Spot Run” to a level computers can understand – machine language.     CHARACTER:  The character level is what is rendered by the computer.  A “Character Set” or “Code Page” contains 256 characters, both printable and unprintable.  Each character represents 1 BYTE of data.  For example, the character string “See Spot Run” is 12 Bytes long, exclusive of the quotation marks.  Remember, a SPACE is an unprintable character, but it still requires a byte.  In the example I have used the default Windows character set, ASCII, which you can see here:  http://www.asciitable.com/ HEX:  Hex is short for hexadecimal, or Base 16.  Humans are comfortable thinking in base ten, perhaps because they have 10 fingers and 10 toes; fingers and toes are called digits, so it’s not much of a stretch.  Computers think in Base 16, with numeric values ranging from zero to fifteen, or 0 – F.  Each decimal place has a possible 16 values as opposed to a possible 10 values in base 10.  Therefore, the number 10 in Hex is equal to the number 16 in Decimal.  DECIMAL:  The Decimal conversion is strictly for us humans to use for calculations and conversions.  It is much easier for us humans to calculate that [30 – 10 = 20] in decimal than it is for us to calculate [1E – A = 14] in Hex.  In the old days, an error in a program could be found by determining the displacement from the entry point of a module.  Since those values were dumped from the computers head, they were in hex. A programmer needed to convert them to decimal, do the equation and convert back to hex.  This gets into relative and absolute addressing, a topic for another day.  BINARY:  Binary, or machine code, is where any value can be expressed in 1s and 0s.  It is really Base 2, because each decimal place can have a possibility of only 2 characters, a 1 or a 0.  In Binary, the number 10 is equal to the number 2 in decimal. Why only 1s and 0s?  Very simply, computers are made up of lots and lots of transistors which at any given moment can be ON ( 1 ) or OFF ( 0 ).  Each transistor is a bit, and the order that the transistors fire (or not fire) is what distinguishes one value from  another in the computers head (or CPU).  Consider 32 bit vs 64 bit processing…..a 64 bit processor has the capability to read 64 transistors at a time.  A 32 bit processor can only read half as many at a time, so in theory the 64 bit processor should be much faster.  There are many more factors involved in CPU performance, but that is the fundamental difference.    DECIMAL HEX BINARY 0 0 0000 1 1 0001 2 2 0010 3 3 0011 4 4 0100 5 5 0101 6 6 0110 7 7 0111 8 8 1000 9 9 1001 10 A 1010 11 B 1011 12 C 1100 13 D 1101 14 E 1110 15 F 1111   Remember that each character is a BYTE, there are 2 HEX characters in a byte (called nibbles) and 8 BITS in a byte.  I hope you enjoyed reading about the theory of data processing.  This is just a high-level explanation, and there is much more to be learned.  It is safe to say that, no matter how advanced our programming languages and visual studios become, they are nothing more than a way to interpret bits and bytes.  There is nothing like the joy of hex to get the mind racing.

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• What Keeps You from Changing Your Public IP Address and Wreaking Havoc on the Internet?

  - by Jason Fitzpatrick

  What exactly is preventing you (or anyone else) from changing their IP address and causing all sorts of headaches for ISPs and other Internet users? Today’s Question & Answer session comes to us courtesy of SuperUser—a subdivision of Stack Exchange, a community-driven grouping of Q&A web sites. The Question SuperUser reader Whitemage is curious about what’s preventing him from wantonly changing his IP address and causing trouble: An interesting question was asked of me and I did not know what to answer. So I’ll ask here. Let’s say I subscribed to an ISP and I’m using cable internet access. The ISP gives me a public IP address of 60.61.62.63. What keeps me from changing this IP address to, let’s say, 60.61.62.75, and messing with another consumer’s internet access? For the sake of this argument, let’s say that this other IP address is also owned by the same ISP. Also, let’s assume that it’s possible for me to go into the cable modem settings and manually change the IP address. Under a business contract where you are allocated static addresses, you are also assigned a default gateway, a network address and a broadcast address. So that’s 3 addresses the ISP “loses” to you. That seems very wasteful for dynamically assigned IP addresses, which the majority of customers are. Could they simply be using static arps? ACLs? Other simple mechanisms? Two things to investigate here, why can’t we just go around changing our addresses, and is the assignment process as wasteful as it seems? The Answer SuperUser contributor Moses offers some insight: Cable modems aren’t like your home router (ie. they don’t have a web interface with simple point-and-click buttons that any kid can “hack” into). Cable modems are “looked up” and located by their MAC address by the ISP, and are typically accessed by technicians using proprietary software that only they have access to, that only runs on their servers, and therefore can’t really be stolen. Cable modems also authenticate and cross-check settings with the ISPs servers. The server has to tell the modem whether it’s settings (and location on the cable network) are valid, and simply sets it to what the ISP has it set it for (bandwidth, DHCP allocations, etc). For instance, when you tell your ISP “I would like a static IP, please.”, they allocate one to the modem through their servers, and the modem allows you to use that IP. Same with bandwidth changes, for instance. To do what you are suggesting, you would likely have to break into the servers at the ISP and change what it has set up for your modem. Could they simply be using static arps? ACLs? Other simple mechanisms? Every ISP is different, both in practice and how close they are with the larger network that is providing service to them. Depending on those factors, they could be using a combination of ACL and static ARP. It also depends on the technology in the cable network itself. The ISP I worked for used some form of ACL, but that knowledge was a little beyond my paygrade. I only got to work with the technician’s interface and do routine maintenance and service changes. What keeps me from changing this IP address to, let’s say, 60.61.62.75 and mess with another consumer’s internet access? Given the above, what keeps you from changing your IP to one that your ISP hasn’t specifically given to you is a server that is instructing your modem what it can and can’t do. Even if you somehow broke into the modem, if 60.61.62.75 is already allocated to another customer, then the server will simply tell your modem that it can’t have it. David Schwartz offers some additional insight with a link to a white paper for the really curious: Most modern ISPs (last 13 years or so) will not accept traffic from a customer connection with a source IP address they would not route to that customer were it the destination IP address. This is called “reverse path forwarding”. See BCP 38. Have something to add to the explanation? Sound off in the the comments. Want to read more answers from other tech-savvy Stack Exchange users? Check out the full discussion thread here.     

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• Unable to keep the connecting using a wireless bridge

  - by dan

  I am running Ubuntu 12.04 on a dell inspiron desktop (core 2 duo) and am using wicd to manage my network/wifi. I've found that the WiFi card in the machine has trouble staying connected to my router (I believe this is a function of distance between the two), so I've taken an old Belkin F5d7231 wireless router and installed dd-wrt on it to use as a wireless bridge hoping that it will have better reception. I think everything up through the wireless bridge is working OK since I have no problems accessing the internet through it with my MacBook. The problem arises when I try to hook the ubuntu machine up to the wireless bridge. It will connect for a few minutes, but it will quickly disconnect without clear triggering event; it may be more likely to disconnect if there is a heavy traffic load going over it (could be something as simple as "cat big_text_file" in an ssh session). I've tried switching from dhclient to dhcpcd without much improvement. Here is the output from the syslog when it connects: Jun 30 17:10:08 Chicabuntu dhcpcd[28278]: wlan1: dhcpcd not running Jun 30 17:10:08 Chicabuntu dhcpcd[28278]: wlan1: exiting Jun 30 17:10:08 Chicabuntu dhcpcd[28312]: eth0: dhcpcd not running Jun 30 17:10:08 Chicabuntu dhcpcd[28312]: eth0: exiting Jun 30 17:10:08 Chicabuntu avahi-daemon[1041]: Interface eth0.IPv6 no longer relevant for mDNS. Jun 30 17:10:08 Chicabuntu avahi-daemon[1041]: Leaving mDNS multicast group on interface eth0.IPv6 with address fe80::21c:c4ff:fe31:1a83. Jun 30 17:10:08 Chicabuntu avahi-daemon[1041]: Withdrawing address record for fe80::21c:c4ff:fe31:1a83 on eth0. Jun 30 17:10:08 Chicabuntu kernel: [15184.976127] tg3 0000:3f:00.0: irq 44 for MSI/MSI-X Jun 30 17:10:08 Chicabuntu kernel: [15185.010805] ADDRCONF(NETDEV_UP): eth0: link is not ready Jun 30 17:10:08 Chicabuntu dhcpcd[28347]: eth0: dhcpcd not running Jun 30 17:10:08 Chicabuntu dhcpcd[28347]: eth0: exiting Jun 30 17:10:08 Chicabuntu kernel: [15185.180156] tg3 0000:3f:00.0: irq 44 for MSI/MSI-X Jun 30 17:10:08 Chicabuntu kernel: [15185.212785] ADDRCONF(NETDEV_UP): eth0: link is not ready Jun 30 17:10:10 Chicabuntu kernel: [15187.027445] tg3 0000:3f:00.0: eth0: Link is up at 100 Mbps, full duplex Jun 30 17:10:10 Chicabuntu kernel: [15187.027452] tg3 0000:3f:00.0: eth0: Flow control is on for TX and on for RX Jun 30 17:10:10 Chicabuntu kernel: [15187.028300] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready Jun 30 17:10:10 Chicabuntu dhcpcd[28353]: eth0: dhcpcd 3.2.3 starting Jun 30 17:10:10 Chicabuntu dhcpcd[28353]: eth0: hardware address = 00:1c:c4:31:1a:83 Jun 30 17:10:10 Chicabuntu dhcpcd[28353]: eth0: DUID = 00:01:00:01:17:81:85:79:00:1c:c4:31:1a:83 Jun 30 17:10:10 Chicabuntu dhcpcd[28353]: eth0: broadcasting for a lease Jun 30 17:10:11 Chicabuntu avahi-daemon[1041]: Joining mDNS multicast group on interface eth0.IPv6 with address fe80::21c:c4ff:fe31:1a83. Jun 30 17:10:11 Chicabuntu avahi-daemon[1041]: New relevant interface eth0.IPv6 for mDNS. Jun 30 17:10:11 Chicabuntu avahi-daemon[1041]: Registering new address record for fe80::21c:c4ff:fe31:1a83 on eth0.*. Jun 30 17:10:20 Chicabuntu kernel: [15197.568016] eth0: no IPv6 routers present Jun 30 17:10:29 Chicabuntu dhcpcd[28353]: eth0: offered 192.168.1.111 from 192.168.1.254 Jun 30 17:10:29 Chicabuntu dhcpcd[28353]: eth0: checking 192.168.1.111 is available on attached networks Jun 30 17:10:30 Chicabuntu dhcpcd[28353]: eth0: leased 192.168.1.111 for 86400 seconds Jun 30 17:10:30 Chicabuntu dhcpcd[28353]: eth0: adding IP address 192.168.1.111/24 Jun 30 17:10:30 Chicabuntu avahi-daemon[1041]: Joining mDNS multicast group on interface eth0.IPv4 with address 192.168.1.111. Jun 30 17:10:30 Chicabuntu dhcpcd[28353]: eth0: adding default route via 192.168.1.254 metric 0 Jun 30 17:10:30 Chicabuntu dhcpcd[28353]: eth0: exiting Jun 30 17:10:30 Chicabuntu avahi-daemon[1041]: New relevant interface eth0.IPv4 for mDNS. Jun 30 17:10:30 Chicabuntu avahi-daemon[1041]: Registering new address record for 192.168.1.111 on eth0.IPv4. Jun 30 17:10:30 Chicabuntu dhcpcd.sh: interface eth0 has been configured with new IP=192.168.1.111 Jun 30 17:10:39 Chicabuntu ntpdate[28439]: adjust time server 91.189.94.4 offset 0.001915 sec And here is the syslog from when it shuts down the connection without reason: Jun 30 17:12:15 Chicabuntu kernel: [15312.575455] tg3 0000:3f:00.0: eth0: Link is down Jun 30 17:12:16 Chicabuntu dhcpcd[28603]: eth0: sending signal 1 to pid 28361 Jun 30 17:12:16 Chicabuntu dhcpcd[28361]: eth0: received SIGHUP, releasing lease Jun 30 17:12:16 Chicabuntu dhcpcd[28603]: eth0: exiting Jun 30 17:12:16 Chicabuntu avahi-daemon[1041]: Withdrawing address record for 192.168.1.111 on eth0. Jun 30 17:12:16 Chicabuntu avahi-daemon[1041]: Leaving mDNS multicast group on interface eth0.IPv4 with address 192.168.1.111. Jun 30 17:12:16 Chicabuntu avahi-daemon[1041]: Interface eth0.IPv4 no longer relevant for mDNS. Jun 30 17:12:16 Chicabuntu dhcpcd[28361]: eth0: removing default route via 192.168.1.254 metric 0 Jun 30 17:12:16 Chicabuntu avahi-daemon[1041]: Interface eth0.IPv6 no longer relevant for mDNS. Jun 30 17:12:16 Chicabuntu avahi-daemon[1041]: Leaving mDNS multicast group on interface eth0.IPv6 with address fe80::21c:c4ff:fe31:1a83. Jun 30 17:12:16 Chicabuntu avahi-daemon[1041]: Withdrawing address record for fe80::21c:c4ff:fe31:1a83 on eth0. Jun 30 17:12:16 Chicabuntu dhcpcd[28361]: eth0: netlink: No such process Jun 30 17:12:16 Chicabuntu dhcpcd[28361]: eth0: removing IP address 192.168.1.111/24 Jun 30 17:12:16 Chicabuntu dhcpcd[28361]: eth0: netlink: Cannot assign requested address Jun 30 17:12:16 Chicabuntu dhcpcd[28361]: eth0: exiting Jun 30 17:12:16 Chicabuntu dhcpcd.sh: interface eth0 has been brought down Jun 30 17:12:17 Chicabuntu kernel: [15313.612141] tg3 0000:3f:00.0: irq 44 for MSI/MSI-X Jun 30 17:12:17 Chicabuntu kernel: [15313.644703] ADDRCONF(NETDEV_UP): eth0: link is not ready Jun 30 17:12:17 Chicabuntu dhcpcd[28674]: wlan1: dhcpcd not running Jun 30 17:12:17 Chicabuntu dhcpcd[28674]: wlan1: exiting Jun 30 17:12:17 Chicabuntu dhcpcd[28708]: eth0: dhcpcd not running Jun 30 17:12:17 Chicabuntu dhcpcd[28708]: eth0: exiting Jun 30 17:12:17 Chicabuntu kernel: [15313.912147] tg3 0000:3f:00.0: irq 44 for MSI/MSI-X Jun 30 17:12:17 Chicabuntu kernel: [15313.944746] ADDRCONF(NETDEV_UP): eth0: link is not ready Jun 30 17:12:18 Chicabuntu kernel: [15315.592569] tg3 0000:3f:00.0: eth0: Link is up at 100 Mbps, full duplex Jun 30 17:12:18 Chicabuntu kernel: [15315.592576] tg3 0000:3f:00.0: eth0: Flow control is on for TX and on for RX Jun 30 17:12:18 Chicabuntu kernel: [15315.593399] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready Jun 30 17:12:20 Chicabuntu avahi-daemon[1041]: Joining mDNS multicast group on interface eth0.IPv6 with address fe80::21c:c4ff:fe31:1a83. Jun 30 17:12:20 Chicabuntu avahi-daemon[1041]: New relevant interface eth0.IPv6 for mDNS. Jun 30 17:12:20 Chicabuntu avahi-daemon[1041]: Registering new address record for fe80::21c:c4ff:fe31:1a83 on eth0.*. Jun 30 17:12:29 Chicabuntu kernel: [15325.680019] eth0: no IPv6 routers present If this isn't useful, I can also post the wicd log, but that is kind of long. If anyone could help me I would be eternally grateful.

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