Search Results

Search found 12247 results on 490 pages for 'non profit'.

Page 95/490 | < Previous Page | 91 92 93 94 95 96 97 98 99 100 101 102  | Next Page >

  • The #OOW Party May Over...

    - by user462779
    ...but there's no reason why we can't look forward to the next one! It's going to take all week for me to catch up on last week's neglected email, sort through the freshly-collected business cards, and generally make sense of the mad dash that is Oracle OpenWorld. So I've been playing this amazing video (produced by Lozano Productions) to remind me of the last business/IT conference marathon I survived: Collaborate 2012. It was an amazing event where we officially launched the new design of Profit and enjoyed a drink with some of our closest friends--Oracle partners, customers, and peers. Many thanks to those who came out to celebrate and who continue to help make Profit a success. It was a great time that resulted in a lot of great new work and new relationships. So I'm taking a time out to remember that the hard work is worth it. See you in Denver next year!

    Read the article

  • Histoire : le fabuleux destin de la calculatrice graphique née dans la clandestinité de l'Apple sans Steve Jobs

    Histoire : le fabuleux destin de la calculatrice graphique Née dans la clandestinité de l'Apple sans Steve Jobs Entre le licenciement de Steve Jobs par la bande à John Sculley en 1985, et son retour en 1996, bien des histoires se sont passées à Apple, que l'Histoire n'a pas forcément choisi d'oublier. Cette période, marquée par une perte du sens de produit d'Apple au profit de la recherche du... profit, a conduit à la multiplication de produits, la scission entre les équipes et une dilatation des développements amenant l'entreprise au bord du gouffre. La suite de l'histoire, on la connaît. Mais d'un tel marasme, de bonnes choses sont nées. Comme NuCalc, plus commu...

    Read the article

  • How can I set up private, per-user sections on Joomla?

    - by Michael Paulukonis
    For this weekend's GiveCamp project, my team has been tasked with adding some functionality to an existing Joomla-powered website for a non-profit. A certain type of user will login, and have access to a personal area where they can upload files, check for messages, see tasks that have been assigned, etc. Each user would have their own area. They would not be creating pages, and their information would only be visible to themselves (or a site-administrator, of course. No sort of weird HIPAA privacy involved). None of us have worked with Joomla before, but we'd like to help this non-profit. We're not sure if we're searching using the wrong terms, or if we're just not finding it. Is such a solution possible in Joomla? And/or are we better off building some standalone solution that interfaces with the same mySQL database as Joomla?

    Read the article

  • Am I personally liable for bugs in medical software I've developed as an employee? [closed]

    - by user466406
    Some background: I'm employed at a small, Australia-based web agency that is dipping it's toe into Mobile Application development (iOS). The project that I'm working on provides a way for users to save medication dosage information which is sync'd with a backend server. Users must agree to ToS, Disclaimer etc before using the application. This is my first iOS application, and the project is currently over budget. As a result, management is not devoting the resources to Q&A and is pushing instead for more features. I am an employee of the agency, that has been contracted by a non-for-profit. The application will probably be released under our agency's name, but we also have the option of releasing it as the not-for-profit. My question is, if there are bugs found in the application, and as a result a user takes an incorrect dosage of a medication, am I personally liable? Is there anything that I can or should do in order to protect myself personally?

    Read the article

  • How to capture child links clicked using jquery?

    - by user244394
    I am trying to capture the event when a child element link is clicked and add class called "highlightchild" to it. Also I want to check if there are any child element link exist or not, if no child element exits ie "third level" highlight with "highlightparent" the parent. How can I do that using jquery? $(document).ready(function() { $('.menu ul').hide(); $('.menu .arrowUp').click(function() { $('.menu ul').hide(); $(this).find(".third-level").toggle(); }); }); html <ul class="menu"> <li class="arrowUp"><a href="#">link1</a> <ul class="third-level" > <!-- third level non-active --> <li class="arrowUp"><a href="/somelink/">Some Link</a></li> </ul> </li> <li class="arrowUp"><a href="#">link2</a> <ul class="third-level" > <!-- third level non-active --> <li class="arrowUp"><a href="/links2/">some Links 2</a></li> </ul> </li> <li class="arrowUp"><a href="#">link3</a> <ul class="third-level" > <!-- third level non-active --> <li class="arrowUp"><a href="/Agri/">Agricultural</a></li> <!-- third level non-active --> <li class="arrowUp"><a href="/sugar/">Sugar</a></li> <!-- third level non-active --> <li class="arrowUp"><a href="/bbc/">Coffee</a></li> <!-- third level non-active --> <li class="arrowUp"><a href="/cnn/">Energy</a></li> <!-- third level non-active --> <li class="arrowUp"><a href="funstuff">Fun stuff</a></li> </ul> </li> <li class="arrowUp"><a href="#">link4</a></li> <li class="arrowUp"><a href="#">link5</a></li> <li class="arrowUp"><a href="#">link6</a></li> </ul>

    Read the article

  • Oracle Solaris: Zones on Shared Storage

    - by Jeff Victor
    Oracle Solaris 11.1 has several new features. At oracle.com you can find a detailed list. One of the significant new features, and the most significant new feature releated to Oracle Solaris Zones, is casually called "Zones on Shared Storage" or simply ZOSS (rhymes with "moss"). ZOSS offers much more flexibility because you can store Solaris Zones on shared storage (surprise!) so that you can perform quick and easy migration of a zone from one system to another. This blog entry describes and demonstrates the use of ZOSS. ZOSS provides complete support for a Solaris Zone that is stored on "shared storage." In this case, "shared storage" refers to fiber channel (FC) or iSCSI devices, although there is one lone exception that I will demonstrate soon. The primary intent is to enable you to store a zone on FC or iSCSI storage so that it can be migrated from one host computer to another much more easily and safely than in the past. With this blog entry, I wanted to make it easy for you to try this yourself. I couldn't assume that you have a SAN available - which is a good thing, because neither do I! What could I use, instead? [There he goes, foreshadowing again... -Ed.] Developing this entry reinforced the lesson that the solution to every lab problem is VirtualBox. Oracle VM VirtualBox (its formal name) helps here in a couple of important ways. It offers the ability to easily install multiple copies of Solaris as guests on top of any popular system (Microsoft Windows, MacOS, Solaris, Oracle Linux (and other Linuxes) etc.). It also offers the ability to create a separate virtual disk drive (VDI) that appears as a local hard disk to a guest. This virtual disk can be moved very easily from one guest to another. In other words, you can follow the steps below on a laptop or larger x86 system. Please note that the ability to use ZOSS to store a zone on a local disk is very useful for a lab environment, but not so useful for production. I do not suggest regularly moving disk drives among computers. In the method I describe below, that virtual hard disk will contain the zone that will be migrated among the (virtual) hosts. In production, you would use FC or iSCSI LUNs instead. The zonecfg(1M) man page details the syntax for each of the three types of devices. Why Migrate? Why is the migration of virtual servers important? Some of the most common reasons are: Moving a workload to a different computer so that the original computer can be turned off for extensive maintenance. Moving a workload to a larger system because the workload has outgrown its original system. If the workload runs in an environment (such as a Solaris Zone) that is stored on shared storage, you can restore the service of the workload on an alternate computer if the original computer has failed and will not reboot. You can simplify lifecycle management of a workload by developing it on a laptop, migrating it to a test platform when it's ready, and finally moving it to a production system. Concepts For ZOSS, the important new concept is named "rootzpool". You can read about it in the zonecfg(1M) man page, but here's the short version: it's the backing store (hard disk(s), or LUN(s)) that will be used to make a ZFS zpool - the zpool that will hold the zone. This zpool: contains the zone's Solaris content, i.e. the root file system does not contain any content not related to the zone can only be mounted by one Solaris instance at a time Method Overview Here is a brief list of the steps to create a zone on shared storage and migrate it. The next section shows the commands and output. You will need a host system with an x86 CPU (hopefully at least a couple of CPU cores), at least 2GB of RAM, and at least 25GB of free disk space. (The steps below will not actually use 25GB of disk space, but I don't want to lead you down a path that ends in a big sign that says "Your HDD is full. Good luck!") Configure the zone on both systems, specifying the rootzpool that both will use. The best way is to configure it on one system and then copy the output of "zonecfg export" to the other system to be used as input to zonecfg. This method reduces the chances of pilot error. (It is not necessary to configure the zone on both systems before creating it. You can configure this zone in multiple places, whenever you want, and migrate it to one of those places at any time - as long as those systems all have access to the shared storage.) Install the zone on one system, onto shared storage. Boot the zone. Provide system configuration information to the zone. (In the Real World(tm) you will usually automate this step.) Shutdown the zone. Detach the zone from the original system. Attach the zone to its new "home" system. Boot the zone. The zone can be used normally, and even migrated back, or to a different system. Details The rest of this shows the commands and output. The two hostnames are "sysA" and "sysB". Note that each Solaris guest might use a different device name for the VDI that they share. I used the device names shown below, but you must discover the device name(s) after booting each guest. In a production environment you would also discover the device name first and then configure the zone with that name. Fortunately, you can use the command "zpool import" or "format" to discover the device on the "new" host for the zone. The first steps create the VirtualBox guests and the shared disk drive. I describe the steps here without demonstrating them. Download VirtualBox and install it using a method normal for your host OS. You can read the complete instructions. Create two VirtualBox guests, each to run Solaris 11.1. Each will use its own VDI as its root disk. Install Solaris 11.1 in each guest.Install Solaris 11.1 in each guest. To install a Solaris 11.1 guest, you can either download a pre-built VirtualBox guest, and import it, or install Solaris 11.1 from the "text install" media. If you use the latter method, after booting you will not see a windowing system. To install the GUI and other important things, login and run "pkg install solaris-desktop" and take a break while it installs those important things. Life is usually easier if you install the VirtualBox Guest Additions because then you can copy and paste between the host and guests, etc. You can find the guest additions in the folder matching the version of VirtualBox you are using. You can also read the instructions for installing the guest additions. To create the zone's shared VDI in VirtualBox, you can open the storage configuration for one of the two guests, select the SATA controller, and click on the "Add Hard Disk" icon nearby. Choose "Create New Disk" and specify an appropriate path name for the file that will contain the VDI. The shared VDI must be at least 1.5 GB. Note that the guest must be stopped to do this. Add that VDI to the other guest - using its Storage configuration - so that each can access it while running. The steps start out the same, except that you choose "Choose Existing Disk" instead of "Create New Disk." Because the disk is configured on both of them, VirtualBox prevents you from running both guests at the same time. Identify device names of that VDI, in each of the guests. Solaris chooses the name based on existing devices. The names may be the same, or may be different from each other. This step is shown below as "Step 1." Assumptions In the example shown below, I make these assumptions. The guest that will own the zone at the beginning is named sysA. The guest that will own the zone after the first migration is named sysB. On sysA, the shared disk is named /dev/dsk/c7t2d0 On sysB, the shared disk is named /dev/dsk/c7t3d0 (Finally!) The Steps Step 1) Determine the name of the disk that will move back and forth between the systems. root@sysA:~# format Searching for disks...done AVAILABLE DISK SELECTIONS: 0. c7t0d0 /pci@0,0/pci8086,2829@d/disk@0,0 1. c7t2d0 /pci@0,0/pci8086,2829@d/disk@2,0 Specify disk (enter its number): ^D Step 2) The first thing to do is partition and label the disk. The magic needed to write an EFI label is not overly complicated. root@sysA:~# format -e c7t2d0 selecting c7t2d0 [disk formatted] FORMAT MENU: ... format fdisk No fdisk table exists. The default partition for the disk is: a 100% "SOLARIS System" partition Type "y" to accept the default partition, otherwise type "n" to edit the partition table. n SELECT ONE OF THE FOLLOWING: ... Enter Selection: 1 ... G=EFI_SYS 0=Exit? f SELECT ONE... ... 6 format label ... Specify Label type[1]: 1 Ready to label disk, continue? y format quit root@sysA:~# ls /dev/dsk/c7t2d0 /dev/dsk/c7t2d0 Step 3) Configure zone1 on sysA. root@sysA:~# zonecfg -z zone1 Use 'create' to begin configuring a new zone. zonecfg:zone1 create create: Using system default template 'SYSdefault' zonecfg:zone1 set zonename=zone1 zonecfg:zone1 set zonepath=/zones/zone1 zonecfg:zone1 add rootzpool zonecfg:zone1:rootzpool add storage dev:dsk/c7t2d0 zonecfg:zone1:rootzpool end zonecfg:zone1 exit root@sysA:~# oot@sysA:~# zonecfg -z zone1 info zonename: zone1 zonepath: /zones/zone1 brand: solaris autoboot: false bootargs: file-mac-profile: pool: limitpriv: scheduling-class: ip-type: exclusive hostid: fs-allowed: anet: ... rootzpool: storage: dev:dsk/c7t2d0 Step 4) Install the zone. This step takes the most time, but you can wander off for a snack or a few laps around the gym - or both! (Just not at the same time...) root@sysA:~# zoneadm -z zone1 install Created zone zpool: zone1_rpool Progress being logged to /var/log/zones/zoneadm.20121022T163634Z.zone1.install Image: Preparing at /zones/zone1/root. AI Manifest: /tmp/manifest.xml.RXaycg SC Profile: /usr/share/auto_install/sc_profiles/enable_sci.xml Zonename: zone1 Installation: Starting ... Creating IPS image Startup linked: 1/1 done Installing packages from: solaris origin: http://pkg.us.oracle.com/support/ DOWNLOAD PKGS FILES XFER (MB) SPEED Completed 183/183 33556/33556 222.2/222.2 2.8M/s PHASE ITEMS Installing new actions 46825/46825 Updating package state database Done Updating image state Done Creating fast lookup database Done Installation: Succeeded Note: Man pages can be obtained by installing pkg:/system/manual done. Done: Installation completed in 1696.847 seconds. Next Steps: Boot the zone, then log into the zone console (zlogin -C) to complete the configuration process. Log saved in non-global zone as /zones/zone1/root/var/log/zones/zoneadm.20121022T163634Z.zone1.install Step 5) Boot the Zone. root@sysA:~# zoneadm -z zone1 boot Step 6) Login to zone's console to complete the specification of system information. root@sysA:~# zlogin -C zone1 Answer the usual questions and wait for a login prompt. Then you can end the console session with the usual "~." incantation. Step 7) Shutdown the zone so it can be "moved." root@sysA:~# zoneadm -z zone1 shutdown Step 8) Detach the zone so that the original global zone can't use it. root@sysA:~# zoneadm list -cv ID NAME STATUS PATH BRAND IP 0 global running / solaris shared - zone1 installed /zones/zone1 solaris excl root@sysA:~# zpool list NAME SIZE ALLOC FREE CAP DEDUP HEALTH ALTROOT rpool 17.6G 11.2G 6.47G 63% 1.00x ONLINE - zone1_rpool 1.98G 484M 1.51G 23% 1.00x ONLINE - root@sysA:~# zoneadm -z zone1 detach Exported zone zpool: zone1_rpool Step 9) Review the result and shutdown sysA so that sysB can use the shared disk. root@sysA:~# zpool list NAME SIZE ALLOC FREE CAP DEDUP HEALTH ALTROOT rpool 17.6G 11.2G 6.47G 63% 1.00x ONLINE - root@sysA:~# zoneadm list -cv ID NAME STATUS PATH BRAND IP 0 global running / solaris shared - zone1 configured /zones/zone1 solaris excl root@sysA:~# init 0 Step 10) Now boot sysB and configure a zone with the parameters shown above in Step 1. (Again, the safest method is to use "zonecfg ... export" on sysA as described in section "Method Overview" above.) The one difference is the name of the rootzpool storage device, which was shown in the list of assumptions, and which you must determine by booting sysB and using the "format" or "zpool import" command. When that is done, you should see the output shown next. (I used the same zonename - "zone1" - in this example, but you can choose any valid zonename you want.) root@sysB:~# zoneadm list -cv ID NAME STATUS PATH BRAND IP 0 global running / solaris shared - zone1 configured /zones/zone1 solaris excl root@sysB:~# zonecfg -z zone1 info zonename: zone1 zonepath: /zones/zone1 brand: solaris autoboot: false bootargs: file-mac-profile: pool: limitpriv: scheduling-class: ip-type: exclusive hostid: fs-allowed: anet: linkname: net0 ... rootzpool: storage: dev:dsk/c7t3d0 Step 11) Attaching the zone automatically imports the zpool. root@sysB:~# zoneadm -z zone1 attach Imported zone zpool: zone1_rpool Progress being logged to /var/log/zones/zoneadm.20121022T184034Z.zone1.attach Installing: Using existing zone boot environment Zone BE root dataset: zone1_rpool/rpool/ROOT/solaris Cache: Using /var/pkg/publisher. Updating non-global zone: Linking to image /. Processing linked: 1/1 done Updating non-global zone: Auditing packages. No updates necessary for this image. Updating non-global zone: Zone updated. Result: Attach Succeeded. Log saved in non-global zone as /zones/zone1/root/var/log/zones/zoneadm.20121022T184034Z.zone1.attach root@sysB:~# zoneadm -z zone1 boot root@sysB:~# zlogin zone1 [Connected to zone 'zone1' pts/2] Oracle Corporation SunOS 5.11 11.1 September 2012 Step 12) Now let's migrate the zone back to sysA. Create a file in zone1 so we can verify it exists after we migrate the zone back, then begin migrating it back. root@zone1:~# ls /opt root@zone1:~# touch /opt/fileA root@zone1:~# ls -l /opt/fileA -rw-r--r-- 1 root root 0 Oct 22 14:47 /opt/fileA root@zone1:~# exit logout [Connection to zone 'zone1' pts/2 closed] root@sysB:~# zoneadm -z zone1 shutdown root@sysB:~# zoneadm -z zone1 detach Exported zone zpool: zone1_rpool root@sysB:~# init 0 Step 13) Back on sysA, check the status. Oracle Corporation SunOS 5.11 11.1 September 2012 root@sysA:~# zoneadm list -cv ID NAME STATUS PATH BRAND IP 0 global running / solaris shared - zone1 configured /zones/zone1 solaris excl root@sysA:~# zpool list NAME SIZE ALLOC FREE CAP DEDUP HEALTH ALTROOT rpool 17.6G 11.2G 6.47G 63% 1.00x ONLINE - Step 14) Re-attach the zone back to sysA. root@sysA:~# zoneadm -z zone1 attach Imported zone zpool: zone1_rpool Progress being logged to /var/log/zones/zoneadm.20121022T190441Z.zone1.attach Installing: Using existing zone boot environment Zone BE root dataset: zone1_rpool/rpool/ROOT/solaris Cache: Using /var/pkg/publisher. Updating non-global zone: Linking to image /. Processing linked: 1/1 done Updating non-global zone: Auditing packages. No updates necessary for this image. Updating non-global zone: Zone updated. Result: Attach Succeeded. Log saved in non-global zone as /zones/zone1/root/var/log/zones/zoneadm.20121022T190441Z.zone1.attach root@sysA:~# zpool list NAME SIZE ALLOC FREE CAP DEDUP HEALTH ALTROOT rpool 17.6G 11.2G 6.47G 63% 1.00x ONLINE - zone1_rpool 1.98G 491M 1.51G 24% 1.00x ONLINE - root@sysA:~# zoneadm -z zone1 boot root@sysA:~# zlogin zone1 [Connected to zone 'zone1' pts/2] Oracle Corporation SunOS 5.11 11.1 September 2012 root@zone1:~# zpool list NAME SIZE ALLOC FREE CAP DEDUP HEALTH ALTROOT rpool 1.98G 538M 1.46G 26% 1.00x ONLINE - Step 15) Check for the file created on sysB, earlier. root@zone1:~# ls -l /opt total 1 -rw-r--r-- 1 root root 0 Oct 22 14:47 fileA Next Steps Here is a brief list of some of the fun things you can try next. Add space to the zone by adding a second storage device to the rootzpool. Make sure that you add it to the configurations of both zones! Create a new zone, specifying two disks in the rootzpool when you first configure the zone. When you install that zone, or clone it from another zone, zoneadm uses those two disks to create a mirrored pool. (Three disks will result in a three-way mirror, etc.) Conclusion Hopefully you have seen the ease with which you can now move Solaris Zones from one system to another.

    Read the article

  • Can we have 2 'extension_dir' in php.ini?

    - by Nyxynyx
    When I installed pdo-pgsql, the extension was installed into /usr/lib/php/extensions/no-debug-non-zts-20090626/ and thus not automatically loaded. In php.ini, I have extension_dir = "/usr/local/lib/php/extensions/no-debug-non-zts-20090626" already defined. Snippet of php.ini ; Directory in which the loadable extensions (modules) reside. extension_dir = "/usr/local/lib/php/extensions/no-debug-non-zts-20090626" zend_extension = "/usr/local/IonCube/ioncube_loader_lin_5.3.so" zend_extension = "/usr/local/Zend/lib/Guard-5.5.0/php-5.3.x/ZendGuardLoader.so" extension = "eaccelerator.so" extension = "pdo.so" extension = "pdo_pgsql.so" extension = "pdo_sqlite.so" extension = "sqlite.so" extension = "pdo_mysql.so" Modified to work ; Directory in which the loadable extensions (modules) reside. extension_dir = "/usr/local/lib/php/extensions/no-debug-non-zts-20090626" extension_dir = "/usr/lib/php/extensions/no-debug-non-zts-20090626" zend_extension = "/usr/local/IonCube/ioncube_loader_lin_5.3.so" zend_extension = "/usr/local/Zend/lib/Guard-5.5.0/php-5.3.x/ZendGuardLoader.so" extension = "eaccelerator.so" extension = "pdo.so" extension = "pdo_pgsql.so" extension = "pdo_sqlite.so" extension = "sqlite.so" extension = "pdo_mysql.so" Why did PECL install pdo-pgsql into the 2nd extension directory and not the first? Is it recommended to have 2 extension_dir as shown in the 2nd code snippet above?

    Read the article

  • Strange DNS issue with internal Windows DNS

    - by Brady
    I've encountered a strange issue with our internal Windows DNS infrastructure. We have a website hosted on Amazon EC2 with the DNS running on Amazon Route 53. In the publicly facing DNS we have the wildcard record setup as an A record Alias pointing to an AWS Elastic Load Balancer sitting in front of our EC2 instances. For those who are not aware, the A record Alias behaves like a CNAME record, however no extra lookup is required on the client side (See http://docs.amazonwebservices.com/Route53/latest/DeveloperGuide/CreatingAliasRRSets.html for more information). We have a secondary domain that has the www subdomain as a CNAME pointing to a subdomain on the primary domain, which resolves against the wildcard entry. For example the subdomain www.secondary.com is a CNAME to sub1.primary.com, but there is no explicit entry for sub1.primary.com, so it resolves to wildcard record. This setup work without issue publicly. The issue comes in our internal DNS at our corporate office where we use the same primary domain for some internal only facing sites. In this setup we have two Active Directory DNS servers with one Server 2003 and one Server 2008 R2 instance. The zone is an AD integrated zone, but it is not the AD domain. In the internal DNS we have the wildcard record pointing to a third external domain, that is also hosted on Route 53 with an A record Alias pointing to the same ELB instance. For example, *.primary.com is a CNAME to tertiary.com, so in effect you have www.secondary.com as a CNAME to *.primary.com, which is a CNAME to tertiary.com. In this setup, attempting to resolve www.secondary.com will fail. Clearing the cache on the Server 2003 instance will allow it to resolve once, but subsequent attempts will fail. It fails even with a clean cache against the 2008 R2 server. It seems that only Windows clients are affected. A Mac running OSX Mountain Lion does not experience this issue. I'm even able to replicate the issue using nslookup. Against the 2003 server, with a freshly cleaned cache, I recieve the appropriate response from www.secondary.com: Non-authoritative answer: Name: subdomain.primary.com Address: x.x.x.x (Public IP) Aliases: www.secondary.com Subsequent checks simply return: Non-authoritative answer: Name: www.secondary.com If you set the type to CNAME you get the appropriate responses all the time. www.secondary.com gives you: Non-authoritative answer: www.secondary.com canonical name = subdomain.primary.com And subdomain.primary.com gives you: subdomain.primary.com canonical name = tertiary.com And setting type back to A gives you the appropriate response for tertiary.com: Non-authoritative answer: Name: tertiary.com Address: x.x.x.x (Public IP) Against the 2008 R2 server things are a little different. Even with a clean cache, www.secondary.com returns just: Non-authoritative answer: Name: www.secondary.com The CNAME records are returned appropriately. www.secondary.com returns: Non-authoritative answer: www.secondary.com canonical name = subdomain.primary.com And subdomain.primary.com gives you: subdomain.primary.com canonical name = tertiary.com tertiary.com internet address = x.x.x.x (Public IP) tertiary.com AAAA IPv6 address = x::x (Public IPv6) And setting type back to A gives you the appropriate response for tertiary.com: Non-authoritative answer: Name: tertiary.com Address: x.x.x.x (Public IP) Requests directly against subdomain.primary.com work correctly.

    Read the article

  • Failover tmpfs mirroring. Am I doing it right?

    - by user45286
    My goal is to have a certain directory to be available as tmpfs. There will be some modifications during server uptime in this dir and those modifications must be synced to non-tmpfs persistent dir on HDD over rsync. After server boot the latest version from non-tmpfs persistent dir must be moved to tmpfs and rsync syncing to be started. I'm afraid that rsync will erase non-tmpfs backup if tmpfs dir will be empty.. I'm doing it in this way right now: create tmpfs partition in /etc/fstab cat /etc/rc.local (pseudocode) delete "tmpfs rsync" cronjob from /var/spool/cron/crontabs if there is any cp -r /path/to/non-tmpfs-backup /path/to/tmpfs/dir append /var/spool/cron/crontabs with "tmpfs rsync" cronjob What do you think?

    Read the article

  • Make interchangeable class types via pointer casting only, without having to allocate any new objects?

    - by HostileFork
    UPDATE: I do appreciate "don't want that, want this instead" suggestions. They are useful, especially when provided in context of the motivating scenario. Still...regardless of goodness/badness, I've become curious to find a hard-and-fast "yes that can be done legally in C++11" vs "no it is not possible to do something like that". I want to "alias" an object pointer as another type, for the sole purpose of adding some helper methods. The alias cannot add data members to the underlying class (in fact, the more I can prevent that from happening the better!) All aliases are equally applicable to any object of this type...it's just helpful if the type system can hint which alias is likely the most appropriate. There should be no information about any specific alias that is ever encoded in the underlying object. Hence, I feel like you should be able to "cheat" the type system and just let it be an annotation...checked at compile time, but ultimately irrelevant to the runtime casting. Something along these lines: Node<AccessorFoo>* fooPtr = Node<AccessorFoo>::createViaFactory(); Node<AccessorBar>* barPtr = reinterpret_cast< Node<AccessorBar>* >(fooPtr); Under the hood, the factory method is actually making a NodeBase class, and then using a similar reinterpret_cast to return it as a Node<AccessorFoo>*. The easy way to avoid this is to make these lightweight classes that wrap nodes and are passed around by value. Thus you don't need casting, just Accessor classes that take the node handle to wrap in their constructor: AccessorFoo foo (NodeBase::createViaFactory()); AccessorBar bar (foo.getNode()); But if I don't have to pay for all that, I don't want to. That would involve--for instance--making a special accessor type for each sort of wrapped pointer (AccessorFooShared, AccessorFooUnique, AccessorFooWeak, etc.) Having these typed pointers being aliased for one single pointer-based object identity is preferable, and provides a nice orthogonality. So back to that original question: Node<AccessorFoo>* fooPtr = Node<AccessorFoo>::createViaFactory(); Node<AccessorBar>* barPtr = reinterpret_cast< Node<AccessorBar>* >(fooPtr); Seems like there would be some way to do this that might be ugly but not "break the rules". According to ISO14882:2011(e) 5.2.10-7: An object pointer can be explicitly converted to an object pointer of a different type.70 When a prvalue v of type "pointer to T1" is converted to the type "pointer to cv T2", the result is static_cast(static_cast(v)) if both T1 and T2 are standard-layout types (3.9) and the alignment requirements of T2 are no stricter than those of T1, or if either type is void. Converting a prvalue of type "pointer to T1" to the type "pointer to T2" (where T1 and T2 are object types and where the alignment requirements of T2 are no stricter than those of T1) and back to its original type yields the original pointer value. The result of any other such pointer conversion is unspecified. Drilling into the definition of a "standard-layout class", we find: has no non-static data members of type non-standard-layout-class (or array of such types) or reference, and has no virtual functions (10.3) and no virtual base classes (10.1), and has the same access control (clause 11) for all non-static data members, and has no non-standard-layout base classes, and either has no non-static data member in the most-derived class and at most one base class with non-static data members, or has no base classes with non-static data members, and has no base classes of the same type as the first non-static data member. Sounds like working with something like this would tie my hands a bit with no virtual methods in the accessors or the node. Yet C++11 apparently has std::is_standard_layout to keep things checked. Can this be done safely? Appears to work in gcc-4.7, but I'd like to be sure I'm not invoking undefined behavior.

    Read the article

  • Pagination, Duplicate Content, and SEO

    - by Iamtotallylost
    Please consider a list of items (forum comments, articles, shoes, doesn't matter) which are spread over multiple pages. Different sort orders are supported (by date, by popularity, by price, etc). So, an URL might look like this (I use the query style here to simplify things): /items?id=1234&page=42&sort=popularity /items?id=1234&page=5&sort=date Now, in terms of SEO, I think I should be worried about duplicate content. After all, each item appears at least as many times as there are sort orders. I've seen Matt Cutts talking about the rel=canonical link tag, but he also said that the canonical page should have very similar content. But this is not the case here because page #1 in a non-canonical sort order might have completely different items than page #1 in the canonical sort order. For a given non-canonical page, there is no clear canonical page listing all the same items, so I think rel=canonical won't help here. Then I thought about using the noindex meta tag on all pages with non-canonical sort order, and not using it on all pages with canonical sort order. However, if I use that method, what will happen with backlinks that are going to non-canonical pages -- will they still spread their page rank juice, even though the first page googlebot (or any other crawler) is going to encounter is marked as "noindex"? Can you please comment on my problem and what you think is the best solution? If you think you have a better solution, please consider that 1) I do not want to use Javascript for this, 2) I do not want all the items to be on one page. Thank you.

    Read the article

  • Free Certification Exams for Visual Studio 2010

    - by budugu
    Get promotional codes from herehttp://blogs.msdn.com/gerryo/archive/2010/03/17/register-for-visual-studio-2010-beta-exams.aspx You don’t have to pay anything to take these exams.  These are 100% free. If you pass the exam, you earn the certification just the same as if you took it in a non-beta environment. From Gerry O'Brien’s blog...  2) Is this a real exam? – Yes it is.  Even though the questions are not scored at the time you take the exam, they are real questions and the exam is real.  If you pass the exam, you earn the certification just the same as if you took it in a non-beta environment.  This means you don’t get a pass/fail or score immediately following the exam, but you do get notified 8 to 10 weeks later because we move slow in getting the final scoring in place.  4) What is the main difference between a beta and non-beta exam, besides cost? – The beta exam will show you questions that have not been through a final QA check.  You are that final QA check.  Non-beta exams expose you to 40 or 45 questions and you have a total of two hours to complete it.  The beta exam could expose you to as many as 125 to 150 questions and take up to four hours.   Following exams are for Asp.Net developers Exam 71-515, TS: Web Applications Development with Microsoft .NET Framework 4Exam 71-519: Pro: Designing and Developing Web Applications Using Microsoft .NET Framework 4

    Read the article

  • Lost in Translation

    - by antony.reynolds
    Using the Correct Character Set for the SOA Suite Database A couple of years ago I spent a wonderful week in Tel Aviv helping with the first Oracle BAM implementation in Israel.  Although everyone I interacted spoke better English than I did, the screens and data for the implementation were all in Hebrew, meaning the Hebrew alphabet.  Over the week I learnt to recognize a few Hebrew words, enough to enable me to test what we were doing.  So I knew SOA Suite worked OK with non-English and non-Latin character sets so I was suspicious recently when a customer was having data corruption of non-Latin characters.  On investigation it turned out that the data received correctly in the SOA Suite, but then it was corrupted after being stored in the database. A little investigation revealed that the customer was using the default database character set, which is “WE8ISO8859P1” which, as the name suggests only supports West European 8-bit characters.  What was happening was that when the customer had installed his SOA repository he had ignored the message that his database was not using AL32UTF as the character. After changing the character set on his database he no longer saw the corruption of non-English character data. So the moral of this story is Always install the SOA Repository in to an AL32UTF8 Database This is true for both SOA Suite 10g and 11g.  Ignore it at your peril, because you never know when you will need to support Hebrew, or Japanese or another multi-byte character set.

    Read the article

  • Multiline Replacement With Visual Studio

    - by Alois Kraus
    I had to remove some file headers in a bigger project which were all of the form #region File Header /*[ Compilation unit ----------------------------------------------------------       Name            : Class1.cs       Language        : C#     Creation Date   :      Description     : -----------------------------------------------------------------------------*/ /*] END */ #endregion I know that would be a cool thing to write a simple C# program use a recursive file search, read all lines skip the first n lines and write the files back to disc. But I wanted to test things first before I ruin my source files with one little typo. There comes the Visual Studio Search and Replace in Files dialog into the game. I can test my regular expression to do a multiline match with the Find button before actually breaking anything. And if something goes wrong I have the Undo button.   There is a nice blog post from Paulo Morgado online who deals with Multiline Regular expressions. The Visual Studio Regular expressions are non standard so you have to adapt your usual Regex know how to the other patterns. The pattern I cam finally up with is \#region File Header:b*(.*\n)@\#endregion The Regular expression can be read as \#region File Header Match “#region File Header” \# Escapes the # character since it is a quantifier. :b* After this none or more spaces or tabs can follow (:b stands for space or tab) (.*\n)@ Match anything across lines in a non greedy way (the @ character makes it non greedy) to prevent matching too much until the #endregion somewhere in our source file. \#endregion Match everything until “#endregion” is found I had always knew that Visual Studio can do it but I never bothered to learn the non standard Regex syntax. This is powerful and it is inside Visual Studio since 2005!

    Read the article

  • iPhone c++ development / compiler on a non-Mac PC? (Windows? Linux?)

    - by Ehrann Mehdan
    According to the (in)famous iPhone Developer Program License Agreement change 3.3.1 — Applications may only use Documented APIs in the manner prescribed by Apple and must not use or call any private APIs. Applications must be originally written in Objective-C, C, C++, or JavaScript as executed by the iPhone OS WebKit engine, and only code written in C, C++, and Objective-C may compile and directly link against the Documented APIs (e.g., Applications that link to Documented APIs through an intermediary translation or compatibility layer or tool are prohibited). So it is allowed to develop iPhone apps using C++ My questions Is there a compiler / IDE for developing iPhone apps using C++? Is that compiler / IDE available on non Mac environments? (Windows? Linux?) If not, why? I mean an eclipse C++ plugin for iPhone development will be quite popular, or is there already any serious attempt to do that?

    Read the article

  • unnecessary vertical scrollbar in ie6

    - by tirso
    hi to all does any could help me how to remove unnecessary scroll bar in ie6. I have already put overflow-y: hidden; but still the same output. thanks in advance here is my url http://webberzsoft.com/clients/csslayouttest/template_new.php here is my css * {margin:0;padding:0;}/*for demo purposes only, use a proper reset in your final layout*/ html,body { overflow: auto; height:100%; } body { font-size:100%; background:#777; } #wrapper{ min-height:99%; width: 1240px; margin:0 auto; background: #FFFFFF; border-left:1px solid #000; border-right:1px solid #000; } #header { background:#77F; border-bottom:1px solid #000; height: 70px; } #content{/*just to create top padding without tampering with min-height:100% on #inner*/ padding:10px 0; overflow:hidden;/*contain floats*/ } #left-index { float:left; width:220px; } #right-index { float:right; width:180px; } #middle-index { float:left; width:840px; overflow:hidden;/*contain floats*/ } #left-home { float:left; width:300px; } #right-home { float:right; width:940px; } here is my html <div id="wrapper"> <div id="header"> <h1 align="right">Fixed Header</h1> <h3>IE6 gets an expression</h3> </div> <div id="content"> <div id="left-index"> <h3>Left</h3> <p>Lorem ipsum dolor sit amet consectetuer quis tempus tristique facilisi Vestibulum. Gravida rhoncus orci leo neque mattis felis Sed et tincidunt tellus. Massa ac condimentum elit ridiculus eget urna wisi id Suspendisse ullamcorper.</p> <p>Hendrerit eros ridiculus urna ipsum leo a ac sed tortor nisl. Tincidunt Morbi justo dis odio sit non sapien enim a augue. Sapien odio dui est Sed nisl id id malesuada sagittis et.</p> <p>Lorem ipsum dolor sit amet consectetuer quis tempus tristique facilisi Vestibulum. Gravida rhoncus orci leo neque mattis felis Sed et tincidunt tellus. Massa ac condimentum elit ridiculus eget urna wisi id Suspendisse ullamcorper.</p> <p>Hendrerit eros ridiculus urna ipsum leo a ac sed tortor nisl. Tincidunt Morbi justo dis odio sit non sapien enim a augue. Sapien odio dui est Sed nisl id id malesuada sagittis et.</p> <p>Lorem ipsum dolor sit amet consectetuer quis tempus tristique facilisi Vestibulum. Gravida rhoncus orci leo neque mattis felis Sed et tincidunt tellus. Massa ac condimentum elit ridiculus eget urna wisi id Suspendisse ullamcorper.</p> <p>Hendrerit eros ridiculus urna ipsum leo a ac sed tortor nisl. Tincidunt Morbi justo dis odio sit non sapien enim a augue. Sapien odio dui est Sed nisl id id malesuada sagittis et.</p> <p>Lorem ipsum dolor sit amet consectetuer quis tempus tristique facilisi Vestibulum. Gravida rhoncus orci leo neque mattis felis Sed et tincidunt tellus. Massa ac condimentum elit ridiculus eget urna wisi id Suspendisse ullamcorper.</p> <p>Hendrerit eros ridiculus urna ipsum leo a ac sed tortor nisl. Tincidunt Morbi justo dis odio sit non sapien enim a augue. Sapien odio dui est Sed nisl id id malesuada sagittis et.</p> <p>Lorem ipsum dolor sit amet consectetuer quis tempus tristique facilisi Vestibulum. Gravida rhoncus orci leo neque mattis felis Sed et tincidunt tellus. Massa ac condimentum elit ridiculus eget urna wisi id Suspendisse ullamcorper.</p> <p>Hendrerit eros ridiculus urna ipsum leo a ac sed tortor nisl. Tincidunt Morbi justo dis odio sit non sapien enim a augue. Sapien odio dui est Sed nisl id id malesuada sagittis et.</p> <p>Lorem ipsum dolor sit amet consectetuer quis tempus tristique facilisi Vestibulum. Gravida rhoncus orci leo neque mattis felis Sed et tincidunt tellus. Massa ac condimentum elit ridiculus eget urna wisi id Suspendisse ullamcorper.</p> </div> <div id="middle-index"> <h3>Middle</h3> <p>Lorem ipsum sed pede non adipiscing nulla lacinia ipsum quis ac Integer. Ut consectetuer Cras fringilla Ut non gravida morbi Maecenas semper vel. Vestibulum quis In Nulla Vivamus Sed feugiat Quisque et ipsum tincidunt. Semper vitae cursus metus risus enim gravida tellus id dignissim nec. Justo laoreet dui commodo Integer malesuada vel quis vel consequat metus. Nec id dolor Aliquam Nullam gravida libero montes nunc ante Nulla. Tortor id.</p> <p>Lorem ipsum sed pede non adipiscing nulla lacinia ipsum quis ac Integer. Ut consectetuer Cras fringilla Ut non gravida morbi Maecenas semper vel. Vestibulum quis In Nulla Vivamus Sed feugiat Quisque et ipsum tincidunt. Semper vitae cursus metus risus enim gravida tellus id dignissim nec. Justo laoreet dui commodo Integer malesuada vel quis vel consequat metus. Nec id dolor Aliquam Nullam gravida libero montes nunc ante Nulla. Tortor id.</p> <p class="lgmarg">testing text for scrolling</p> <p class="lgmarg">testing text for scrolling</p> <p class="lgmarg">testing text for scrolling</p> <p class="lgmarg">testing text for scrolling</p> <p class="lgmarg">testing text for scrolling</p> <p class="lgmarg">testing text for scrolling</p> <p class="lgmarg">testing text for scrolling</p> <p class="lgmarg">testing text for scrolling</p> <p class="lgmarg">testing text for scrolling</p> <p class="lgmarg">testing text for scrolling</p> </div> <div id="right-index"> <h3>Right</h3> <p>Lorem ipsum dolor sit amet consectetuer quis tempus tristique facilisi Vestibulum. Gravida rhoncus orci leo neque mattis felis Sed et tincidunt tellus. Massa ac condimentum elit ridiculus eget urna wisi id Suspendisse ullamcorper.</p> <p>Hendrerit eros ridiculus urna ipsum leo a ac sed tortor nisl. Tincidunt Morbi justo dis odio sit non sapien enim a augue. Sapien odio dui est Sed nisl id id malesuada sagittis et.</p> </div> </div><!--end content--> </div>

    Read the article

  • Enable wireless on Dell Inspiron 1300

    - by Simon
    As per subject, I've looked at various resources and attempted ndiswrapper solutions, found a one-click solution that lead to a 404 and this but none works. I've run all updates. Once I managed to lose my wired connection as well and had to reinstall. This is my first hour with Linux. iwconfig gives this before I do anything: lo no wireless extensions. wlan0 IEEE 802.11bg ESSID:off/any Mode:Managed Access Point: Not-Associated Tx-Power=0 dBm Retry long limit:7 RTS thr:off Fragment thr:off Power Management:on eth0 no wireless extens Thanks for responding lspci returns 00:00.0 Host bridge: Intel Corporation Mobile 915GM/PM/GMS/910GML Express Processor to DRAM Controller (rev 03) Subsystem: Dell Device 01c9 Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx- Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort+ >SERR- <PERR- INTx- Latency: 0 Capabilities: <access denied> Kernel driver in use: agpgart-intel 00:02.0 VGA compatible controller: Intel Corporation Mobile 915GM/GMS/910GML Express Graphics Controller (rev 03) (prog-if 00 [VGA controller]) Subsystem: Dell Device 01c9 Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx- Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Interrupt: pin A routed to IRQ 16 Region 0: Memory at dff00000 (32-bit, non-prefetchable) [size=512K] Region 1: I/O ports at eff8 [size=8] Region 2: Memory at c0000000 (32-bit, prefetchable) [size=256M] Region 3: Memory at dfec0000 (32-bit, non-prefetchable) [size=256K] Expansion ROM at <unassigned> [disabled] Capabilities: <access denied> Kernel driver in use: i915 Kernel modules: intelfb, i915 00:02.1 Display controller: Intel Corporation Mobile 915GM/GMS/910GML Express Graphics Controller (rev 03) Subsystem: Dell Device 01c9 Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx- Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Region 0: Memory at dff80000 (32-bit, non-prefetchable) [size=512K] Capabilities: <access denied> 00:1b.0 Audio device: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) High Definition Audio Controller (rev 03) Subsystem: Dell Device 01c9 Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+ Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0, Cache Line Size: 64 bytes Interrupt: pin A routed to IRQ 42 Region 0: Memory at dfebc000 (64-bit, non-prefetchable) [size=16K] Capabilities: <access denied> Kernel driver in use: snd_hda_intel Kernel modules: snd-hda-intel 00:1c.0 PCI bridge: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) PCI Express Port 1 (rev 03) (prog-if 00 [Normal decode]) Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+ Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0, Cache Line Size: 64 bytes Bus: primary=00, secondary=0b, subordinate=0b, sec-latency=0 I/O behind bridge: 00002000-00002fff Memory behind bridge: 30000000-301fffff Prefetchable memory behind bridge: 0000000030200000-00000000303fffff Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- <SERR- <PERR- BridgeCtl: Parity- SERR+ NoISA- VGA- MAbort- >Reset- FastB2B- PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn- Capabilities: <access denied> Kernel driver in use: pcieport Kernel modules: shpchp 00:1c.3 PCI bridge: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) PCI Express Port 4 (rev 03) (prog-if 00 [Normal decode]) Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+ Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0, Cache Line Size: 64 bytes Bus: primary=00, secondary=0c, subordinate=0d, sec-latency=0 I/O behind bridge: 0000d000-0000dfff Memory behind bridge: dfc00000-dfdfffff Prefetchable memory behind bridge: 00000000d0000000-00000000d01fffff Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- <SERR- <PERR- BridgeCtl: Parity- SERR+ NoISA- VGA- MAbort- >Reset- FastB2B- PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn- Capabilities: <access denied> Kernel driver in use: pcieport Kernel modules: shpchp 00:1d.0 USB controller: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) USB UHCI #1 (rev 03) (prog-if 00 [UHCI]) Subsystem: Dell Device 01c9 Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx- Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Interrupt: pin A routed to IRQ 16 Region 4: I/O ports at bf80 [size=32] Kernel driver in use: uhci_hcd 00:1d.1 USB controller: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) USB UHCI #2 (rev 03) (prog-if 00 [UHCI]) Subsystem: Dell Device 01c9 Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx- Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Interrupt: pin B routed to IRQ 17 Region 4: I/O ports at bf60 [size=32] Kernel driver in use: uhci_hcd 00:1d.2 USB controller: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) USB UHCI #3 (rev 03) (prog-if 00 [UHCI]) Subsystem: Dell Device 01c9 Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx- Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Interrupt: pin C routed to IRQ 18 Region 4: I/O ports at bf40 [size=32] Kernel driver in use: uhci_hcd 00:1d.3 USB controller: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) USB UHCI #4 (rev 03) (prog-if 00 [UHCI]) Subsystem: Dell Device 01c9 Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx- Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Interrupt: pin D routed to IRQ 19 Region 4: I/O ports at bf20 [size=32] Kernel driver in use: uhci_hcd 00:1d.7 USB controller: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) USB2 EHCI Controller (rev 03) (prog-if 20 [EHCI]) Subsystem: Dell Device 01c9 Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx- Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Interrupt: pin A routed to IRQ 16 Region 0: Memory at b0000000 (32-bit, non-prefetchable) [size=1K] Capabilities: <access denied> Kernel driver in use: ehci_hcd 00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev d3) (prog-if 01 [Subtractive decode]) Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx- Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Bus: primary=00, secondary=02, subordinate=02, sec-latency=32 I/O behind bridge: 0000f000-00000fff Memory behind bridge: dfb00000-dfbfffff Prefetchable memory behind bridge: 00000000fff00000-00000000000fffff Secondary status: 66MHz- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort+ <SERR- <PERR- BridgeCtl: Parity- SERR+ NoISA- VGA- MAbort- >Reset- FastB2B- PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn- Capabilities: <access denied> 00:1f.0 ISA bridge: Intel Corporation 82801FBM (ICH6M) LPC Interface Bridge (rev 03) Subsystem: Dell Device 01c9 Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx- Status: Cap- 66MHz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Kernel modules: iTCO_wdt, intel-rng 00:1f.1 IDE interface: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) IDE Controller (rev 03) (prog-if 8a [Master SecP PriP]) Subsystem: Dell Device 01c9 Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx- Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Interrupt: pin A routed to IRQ 16 Region 0: I/O ports at 01f0 [size=8] Region 1: I/O ports at 03f4 [size=1] Region 2: I/O ports at 0170 [size=8] Region 3: I/O ports at 0374 [size=1] Region 4: I/O ports at bfa0 [size=16] Kernel driver in use: ata_piix 02:00.0 Ethernet controller: Broadcom Corporation BCM4401-B0 100Base-TX (rev 02) Subsystem: Dell Device 01c9 Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx- Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 64 Interrupt: pin A routed to IRQ 18 Region 0: Memory at dfbfc000 (32-bit, non-prefetchable) [size=8K] Capabilities: <access denied> Kernel driver in use: b44 Kernel modules: b44 02:03.0 Network controller: Broadcom Corporation BCM4318 [AirForce One 54g] 802.11g Wireless LAN Controller (rev 02) Subsystem: Dell Wireless 1370 WLAN Mini-PCI Card Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx- Status: Cap- 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 64 Interrupt: pin A routed to IRQ 17 Region 0: Memory at dfbfe000 (32-bit, non-prefetchable) [size=8K] Kernel driver in use: b43-pci-bridge Kernel modules: ssb and the rfkill shows 0: phy0: Wireless LAN Soft blocked: no Hard blocked: no Just checking addtional drivers. Says no additional driver installed in this system

    Read the article

  • elffile: ELF Specific File Identification Utility

    - by user9154181
    Solaris 11 has a new standard user level command, /usr/bin/elffile. elffile is a variant of the file utility that is focused exclusively on linker related files: ELF objects, archives, and runtime linker configuration files. All other files are simply identified as "non-ELF". The primary advantage of elffile over the existing file utility is in the area of archives — elffile examines the archive members and can produce a summary of the contents, or per-member details. The impetus to add elffile to Solaris came from the effort to extend the format of Solaris archives so that they could grow beyond their previous 32-bit file limits. That work introduced a new archive symbol table format. Now that there was more than one possible format, I thought it would be useful if the file utility could identify which format a given archive is using, leading me to extend the file utility: % cc -c ~/hello.c % ar r foo.a hello.o % file foo.a foo.a: current ar archive, 32-bit symbol table % ar r -S foo.a hello.o % file foo.a foo.a: current ar archive, 64-bit symbol table In turn, this caused me to think about all the things that I would like the file utility to be able to tell me about an archive. In particular, I'd like to be able to know what's inside without having to unpack it. The end result of that train of thought was elffile. Much of the discussion in this article is adapted from the PSARC case I filed for elffile in December 2010: PSARC 2010/432 elffile Why file Is No Good For Archives And Yet Should Not Be Fixed The standard /usr/bin/file utility is not very useful when applied to archives. When identifying an archive, a user typically wants to know 2 things: Is this an archive? Presupposing that the archive contains objects, which is by far the most common use for archives, what platform are the objects for? Are they for sparc or x86? 32 or 64-bit? Some confusing combination from varying platforms? The file utility provides a quick answer to question (1), as it identifies all archives as "current ar archive". It does nothing to answer the more interesting question (2). To answer that question, requires a multi-step process: Extract all archive members Use the file utility on the extracted files, examine the output for each file in turn, and compare the results to generate a suitable summary description. Remove the extracted files It should be easier and more efficient to answer such an obvious question. It would be reasonable to extend the file utility to examine archive contents in place and produce a description. However, there are several reasons why I decided not to do so: The correct design for this feature within the file utility would have file examine each archive member in turn, applying its full abilities to each member. This would be elegant, but also represents a rather dramatic redesign and re-implementation of file. Archives nearly always contain nothing but ELF objects for a single platform, so such generality in the file utility would be of little practical benefit. It is best to avoid adding new options to standard utilities for which other implementations of interest exist. In the case of the file utility, one concern is that we might add an option which later appears in the GNU version of file with a different and incompatible meaning. Indeed, there have been discussions about replacing the Solaris file with the GNU version in the past. This may or may not be desirable, and may or may not ever happen. Either way, I don't want to preclude it. Examining archive members is an O(n) operation, and can be relatively slow with large archives. The file utility is supposed to be a very fast operation. I decided that extending file in this way is overkill, and that an investment in the file utility for better archive support would not be worth the cost. A solution that is more narrowly focused on ELF and other linker related files is really all that we need. The necessary code for doing this already exists within libelf. All that is missing is a small user-level wrapper to make that functionality available at the command line. In that vein, I considered adding an option for this to the elfdump utility. I examined elfdump carefully, and even wrote a prototype implementation. The added code is small and simple, but the conceptual fit with the rest of elfdump is poor. The result complicates elfdump syntax and documentation, definite signs that this functionality does not belong there. And so, I added this functionality as a new user level command. The elffile Command The syntax for this new command is elffile [-s basic | detail | summary] filename... Please see the elffile(1) manpage for additional details. To demonstrate how output from elffile looks, I will use the following files: FileDescription configA runtime linker configuration file produced with crle dwarf.oAn ELF object /etc/passwdA text file mixed.aArchive containing a mixture of ELF and non-ELF members mixed_elf.aArchive containing ELF objects for different machines not_elf.aArchive containing no ELF objects same_elf.aArchive containing a collection of ELF objects for the same machine. This is the most common type of archive. The file utility identifies these files as follows: % file config dwarf.o /etc/passwd mixed.a mixed_elf.a not_elf.a same_elf.a config: Runtime Linking Configuration 64-bit MSB SPARCV9 dwarf.o: ELF 64-bit LSB relocatable AMD64 Version 1 /etc/passwd: ascii text mixed.a: current ar archive, 32-bit symbol table mixed_elf.a: current ar archive, 32-bit symbol table not_elf.a: current ar archive same_elf.a: current ar archive, 32-bit symbol table By default, elffile uses its "summary" output style. This output differs from the output from the file utility in 2 significant ways: Files that are not an ELF object, archive, or runtime linker configuration file are identified as "non-ELF", whereas the file utility attempts further identification for such files. When applied to an archive, the elffile output includes a description of the archive's contents, without requiring member extraction or other additional steps. Applying elffile to the above files: % elffile config dwarf.o /etc/passwd mixed.a mixed_elf.a not_elf.a same_elf.a config: Runtime Linking Configuration 64-bit MSB SPARCV9 dwarf.o: ELF 64-bit LSB relocatable AMD64 Version 1 /etc/passwd: non-ELF mixed.a: current ar archive, 32-bit symbol table, mixed ELF and non-ELF content mixed_elf.a: current ar archive, 32-bit symbol table, mixed ELF content not_elf.a: current ar archive, non-ELF content same_elf.a: current ar archive, 32-bit symbol table, ELF 64-bit LSB relocatable AMD64 Version 1 The output for same_elf.a is of particular interest: The vast majority of archives contain only ELF objects for a single platform, and in this case, the default output from elffile answers both of the questions about archives posed at the beginning of this discussion, in a single efficient step. This makes elffile considerably more useful than file, within the realm of linker-related files. elffile can produce output in two other styles, "basic", and "detail". The basic style produces output that is the same as that from 'file', for linker-related files. The detail style produces per-member identification of archive contents. This can be useful when the archive contents are not homogeneous ELF object, and more information is desired than the summary output provides: % elffile -s detail mixed.a mixed.a: current ar archive, 32-bit symbol table mixed.a(dwarf.o): ELF 32-bit LSB relocatable 80386 Version 1 mixed.a(main.c): non-ELF content mixed.a(main.o): ELF 64-bit LSB relocatable AMD64 Version 1 [SSE]

    Read the article

  • Download and Try Out the New ‘Australis UI’ Test-Build of Firefox for Windows

    - by Asian Angel
    We have all been hearing about the upcoming changes to the UI in Firefox and now the first test build is finally available to try out. Mozilla software engineer Jared Wein has worked hard and put together an unofficial (at the moment) Australis UI build that you can download as a regular installer or as a portable in zip file format. Here is a closer look at the new tab setup in the Australis build. Notice that only the focused tab is non-transparent while the non-active tabs blend nicely into the background. Special Note: Our screenshots were taken in Windows 8, thus the slightly different looking (non-rounded) corners on the app window. The test build only works on Windows at the moment, but you can bet that Linux and MacOS builds are coming in the near future! How to Make Your Laptop Choose a Wired Connection Instead of Wireless HTG Explains: What Is Two-Factor Authentication and Should I Be Using It? HTG Explains: What Is Windows RT and What Does It Mean To Me?

    Read the article

  • Do premium domain names help us with other languages too?

    - by Fabio Milheiro
    It's commonly known that premium domains with one or two relevant keywords may help us improve our rankings in SERPS. But would it be possible that an english premium domain, for example gold.com (no, it's not mine) also helps to drive more non-english traffic (I'm talking about non-english pages ob)? Trying to make my question clear: Let's suppose that I have an english premium domain with a page like this: gold dot com/post/123/gold-is-yellow And decide to have a spanish, portuguese or french version of the site with pages like: gold dot com/es/post/123/el-oro-es-amarillo gold dot com/pt/post/123/o-ouro-e-amarelo gold dot com/fr/post/123/fsdfsdfsdf The fact that my english domain is a premium one and highly relevant for english terms, will also help me to achieve good rankings for non-english searched terms like: oro (spanish) or ouro (portuguese)?

    Read the article

  • Pure virtual or abstract, what's in a name?

    - by Steven Jeuris
    While discussing a question about virtual functions on Stack Overflow, I wondered whether there was any official naming for pure (abstract) and non-pure virtual functions. I always relied on wikipedia for my information, which states that pure and non-pure virtual functions are the general term. Unfortunately, the article doesn't back it up with a origin or references. To quote Jon Skeet's answer to my reply that pure and non-pure are the general term used: @Steven: Hmm... possibly, but I've only ever seen it in the context of C++ before. I suspect anyone talking about them is likely to have a C++ background :) Did the terms originate from C++, or were they first defined or implemented in a earlier language, and are they the 'official' scientific terms?

    Read the article

  • Understanding the value of Customer Experience & Loyalty for the Telecommunications Industry

    - by raul.goycoolea
    Worried by economic woes and market forces, especially in mature markets, communications service providers (CSPs) increasingly focus on improving customer experience. In fact, it seems difficult to find a major message by a C-level executive in the developed world that does not include something on "meeting and exceeding customers' needs". Frequently in customer satisfaction studies by prominent firms, CSPs fall short of the leadership demonstrated by other industries that take customer-centric approaches to their bottom-line strategies. Consider the following:Despite the continued impact of global economic crisis, in July 2010, Apple Computer posted record revenue and net quarterly profit. Those who attribute the results primarily to the iPhone 4 launch should note that Apple also shipped around 30% more Macintosh computers than the same period the previous year. Even sales of the iPod line increased by 8% in a highly commoditized, shrinking media player market. Finally, Apple began selling iPads during the quarter, with total sales of more than 3 million units. What does Apple have that the others lack? Well, some great products (and services) to be sure, but it also excels at customer service and support, marketing, and distribution, and has one of the strongest brands globally. Its products are useful, simple to use, easy to acquire and augment, high quality, and considered very cool. They also evoke such an emotional response from many of Apple's customers, which they turn up their noses at competitive products.In other words, Apple appears to have mastered virtually every aspect of customer experience and the resultant loyalty of its customer base - even in difficult financial times. Through that unwavering customer focus, Apple continues to drive its revenues and profits to new heights. Other customer loyalty leaders like Wal-Mart, Google, Toyota and Honda are also doing well by focusing on customer experience as an essential driver of profitability. Service providers should note this performance and ask themselves how they might leverage the same principles to increase their own profitability. After all, that is what customer experience and loyalty are all about: profitability.To successfully manage all the critical touch points of customer experience, CSPs must shun the one-size-fits-all approach. They can no longer afford to view customer service fundamentally as an act of altruism - which mentality dates back to the industry's civil service days, when CSPs were typically government organizations that were critical to economic development and public safety.As regulators and public officials have pushed, and continue to push, service providers to new heights of reliability - using incentives and punishments - most CSPs already have some of the fundamental building blocks of customer service in place. Yet despite that history and experience, service providers still lag other industries in providing what is seen as good customer service.As we observed in the TMF's 2009 Insights Research report, Customer Experience Management: Driving Loyalty & Profitability there has been resurgence in interest by CSPs. More and more of them have stated ambitions to catch up other industries, and they are realizing that good customer service is a powerful strategy for increasing business performance and profitability, not an act of good will.CSPs are recognizing the connection between customer experience and profitability, as demonstrated in many studies. For example, according to research by Bain & Company, a 5 percent improvement in customer retention rates can yield as much as a 75 percent increase in profits for companies across a range of industries.After decades of customer experience strategy formulation, Bain partner and business author, Frederick Reichheld, considers "would you recommend us to a friend?" as the ultimate question for a customer. How many times have you or your friends recommended an iPod, iPhone or a Mac? What do your children recommend to their peers? Their peers to them?There are certain steps service providers have to take to create more personalized relationships with their customers, as well as reduce churn and increase profitability, all while becoming leaner and more agile. First, they have to define customer experience, we define it as the result of the sum of observations, perceptions, thoughts and feelings arising from interactions and relationships between customers and their service provider(s). Virtually every customer touch point - whether directly or indirectly linked to service providers and their partners - contributes to customer perception, satisfaction, loyalty, and ultimately profitability. Gaining leadership in customer experience and satisfaction will not be a simple task, as it is affected by virtually every customer-facing aspect of the service provider, and in turn impacts the service provider deeply - especially on the all-important bottom line. The scope of issues affecting customer experience is complex and dynamic.With new services, devices and applications extending the basis of customer experience to domains beyond the direct control of the service provider, it is likely to increase in complexity and dynamism.Customer loyalty = increased profitsAs stated earlier, customer experience programs are not fundamentally altruistic exercises, but a strategic means of improving competitiveness and profitability in the short and long term. Loyalty is essential to deriving long term profits from customers.Some of the earliest loyalty programs date back to the 1930s, when packaged goods companies offered embedded coupons for rewards to buyers, and eventually retail chains began offering reward programs to frequent shoppers. These programs continued for decades but were leapfrogged in the 1980s by more aggressive programs from the airlines.This movement was led by American Airlines, which launched the first full-scale loyalty marketing program of the modern era with the AAdvantage frequent flyer scheme. It was the first to reward frequent fliers with notional air miles that could be accumulated and later redeemed for free travel. Figure 1: Opportunities example of Customer loyalty driven profitOther airlines and travel providers were quick to grasp the incredible value of providing customers with an incentive to use their company exclusively. Within a few years, dozens of travel industry companies launched similar initiatives and now loyalty programs are achieving near-ubiquity in many service industries, especially those in which it is difficult to differentiate offerings by product attributes.The belief is that increased profitability will result from customer retention efforts because:•    The cost of acquisition occurs only at the beginning of a relationship: the longer the relationship, the lower the amortized cost;•    Account maintenance costs decline as a percentage of total costs, or as a percentage of revenue, over the lifetime of the relationship;•    Long term customers tend to be less inclined to switch and less price sensitive which can result in stable unit sales volume and increases in dollar-sales volume;•    Long term customers may initiate word-of-mouth promotions and referrals, which cost the company nothing and arguably are the most effective form of advertising;•    Long-term customers are more likely to buy ancillary products and higher margin supplemental products;•    Long term customers tend to be satisfied with their relationship with the company and are less likely to switch to competitors, making market entry or competitors gaining market share difficult;•    Regular customers tend to be less expensive to service, as they are familiar with the processes involved, require less 'education', and are consistent in their order placement;•    Increased customer retention and loyalty makes the employees' jobs easier and more satisfying. In turn, happy employees feed back into higher customer satisfaction in a virtuous circle. Figure 2: The virtuous circle of customer loyaltyFigure 2 represents a high-level example of a virtuous cycle driven by customer satisfaction and loyalty, depicting how superiority in product and service offerings, as well as strong customer support by competent employees, lead to higher sales and ultimately profitability. As stated above, this is not a new concept, but succeeding with it is difficult. It has eluded many a company driven to achieve profitability goals. Of course, for this circle to be virtuous, the customer relationship(s) must be profitable.Trying to maintain the loyalty of unprofitable customers is not a viable business strategy. It is, therefore, important that marketers can assess the profitability of each customer (or customer segment), and either improve or terminate relationships that are not profitable. This means each customer's 'relationship costs' must be understood and compared to their 'relationship revenue'. Customer lifetime value (CLV) is the most commonly used metric here, as it is generally accepted as a representation of exactly how much each customer is worth in monetary terms, and therefore a determinant of exactly how much a service provider should be willing to spend to acquire or retain that customer.CLV models make several simplifying assumptions and often involve the following inputs:•    Churn rate represents the percentage of customers who end their relationship with a company in a given period;•    Retention rate is calculated by subtracting the churn rate percentage from 100;•    Period/horizon equates to the units of time into which a customer relationship can be divided for analysis. A year is the most commonly used period for this purpose. Customer lifetime value is a multi-period calculation, often projecting three to seven years into the future. In practice, analysis beyond this point is viewed as too speculative to be reliable. The model horizon is the number of periods used in the calculation;•    Periodic revenue is the amount of revenue collected from a customer in a given period (though this is often extended across multiple periods into the future to understand lifetime value), such as usage revenue, revenues anticipated from cross and upselling, and often some weighting for referrals by a loyal customer to others; •    Retention cost describes the amount of money the service provider must spend, in a given period, to retain an existing customer. Again, this is often forecast across multiple periods. Retention costs include customer support, billing, promotional incentives and so on;•    Discount rate means the cost of capital used to discount future revenue from a customer. Discounting is an advanced method used in more sophisticated CLV calculations;•    Profit margin is the projected profit as a percentage of revenue for the period. This may be reflected as a percentage of gross or net profit. Again, this is generally projected across the model horizon to understand lifetime value.A strong focus on managing these inputs can help service providers realize stronger customer relationships and profits, but there are some obstacles to overcome in achieving accurate calculations of CLV, such as the complexity of allocating costs across the customer base. There are many costs that serve all customers which must be properly allocated across the base, and often a simple proportional allocation across the whole base or a segment may not accurately reflect the true cost of serving that customer;  This is made worse by the fragmentation of customer information, which is likely to be across a variety of product or operations groups, and may be difficult to aggregate due to different representations.In addition, there is the complexity of account relationships and structures to take into consideration. Complex account structures may not be understood or properly represented. For example, a profitable customer may have a separate account for a second home or another family member, which may appear to be unprofitable. If the service provider cannot relate the two accounts, CLV is not properly represented and any resultant cancellation of the apparently unprofitable account may result in the customer churning from the profitable one.In summary, if service providers are to realize strong customer relationships and their attendant profits, there must be a very strong focus on data management. This needs to be coupled with analytics that help business managers and those who work in customer-facing functions offer highly personalized solutions to customers, while maintaining profitability for the service provider. It's clear that acquiring new customers is expensive. Advertising costs, campaign management expenses, promotional service pricing and discounting, and equipment subsidies make a serious dent in a new customer's profitability. That is especially true given the rising subsidies for Smartphone users, which service providers hope will result in greater profits from profits from data services profitability in future.  The situation is made worse by falling prices and greater competition in mature markets.Customer acquisition through industry consolidation isn't cheap either. A North American service provider spent about $2,000 per subscriber in its acquisition of a smaller company earlier this year. While this has allowed it to leapfrog to become the largest mobile service provider in the country, it required a total investment of more than $28 billion (including assumption of the acquiree's debt).While many operating cost synergies clearly made this deal more attractive to the acquiring company, this is certainly an expensive way to acquire customers: the cost per subscriber in this case is not out of line with the prices others have paid for acquisitions.While growth by acquisition certainly increases overall revenues, it often creates tremendous challenges for profitability. Organic growth through increased customer loyalty and retention is a more effective driver of profit, as well as a stronger predictor of future profitability. Service providers, especially those in mature markets, are increasingly recognizing this and taking steps toward a creating a more personalized, flexible and satisfying experience for their customers.In summary, the clearest path to profitability for companies in virtually all industries is through customer retention and maximization of lifetime value. Service providers would do well to recognize this and focus attention on profitable customer relationships.

    Read the article

  • PTLQueue : a scalable bounded-capacity MPMC queue

    - by Dave
    Title: Fast concurrent MPMC queue -- I've used the following concurrent queue algorithm enough that it warrants a blog entry. I'll sketch out the design of a fast and scalable multiple-producer multiple-consumer (MPSC) concurrent queue called PTLQueue. The queue has bounded capacity and is implemented via a circular array. Bounded capacity can be a useful property if there's a mismatch between producer rates and consumer rates where an unbounded queue might otherwise result in excessive memory consumption by virtue of the container nodes that -- in some queue implementations -- are used to hold values. A bounded-capacity queue can provide flow control between components. Beware, however, that bounded collections can also result in resource deadlock if abused. The put() and take() operators are partial and wait for the collection to become non-full or non-empty, respectively. Put() and take() do not allocate memory, and are not vulnerable to the ABA pathologies. The PTLQueue algorithm can be implemented equally well in C/C++ and Java. Partial operators are often more convenient than total methods. In many use cases if the preconditions aren't met, there's nothing else useful the thread can do, so it may as well wait via a partial method. An exception is in the case of work-stealing queues where a thief might scan a set of queues from which it could potentially steal. Total methods return ASAP with a success-failure indication. (It's tempting to describe a queue or API as blocking or non-blocking instead of partial or total, but non-blocking is already an overloaded concurrency term. Perhaps waiting/non-waiting or patient/impatient might be better terms). It's also trivial to construct partial operators by busy-waiting via total operators, but such constructs may be less efficient than an operator explicitly and intentionally designed to wait. A PTLQueue instance contains an array of slots, where each slot has volatile Turn and MailBox fields. The array has power-of-two length allowing mod/div operations to be replaced by masking. We assume sensible padding and alignment to reduce the impact of false sharing. (On x86 I recommend 128-byte alignment and padding because of the adjacent-sector prefetch facility). Each queue also has PutCursor and TakeCursor cursor variables, each of which should be sequestered as the sole occupant of a cache line or sector. You can opt to use 64-bit integers if concerned about wrap-around aliasing in the cursor variables. Put(null) is considered illegal, but the caller or implementation can easily check for and convert null to a distinguished non-null proxy value if null happens to be a value you'd like to pass. Take() will accordingly convert the proxy value back to null. An advantage of PTLQueue is that you can use atomic fetch-and-increment for the partial methods. We initialize each slot at index I with (Turn=I, MailBox=null). Both cursors are initially 0. All shared variables are considered "volatile" and atomics such as CAS and AtomicFetchAndIncrement are presumed to have bidirectional fence semantics. Finally T is the templated type. I've sketched out a total tryTake() method below that allows the caller to poll the queue. tryPut() has an analogous construction. Zebra stripping : alternating row colors for nice-looking code listings. See also google code "prettify" : https://code.google.com/p/google-code-prettify/ Prettify is a javascript module that yields the HTML/CSS/JS equivalent of pretty-print. -- pre:nth-child(odd) { background-color:#ff0000; } pre:nth-child(even) { background-color:#0000ff; } border-left: 11px solid #ccc; margin: 1.7em 0 1.7em 0.3em; background-color:#BFB; font-size:12px; line-height:65%; " // PTLQueue : Put(v) : // producer : partial method - waits as necessary assert v != null assert Mask = 1 && (Mask & (Mask+1)) == 0 // Document invariants // doorway step // Obtain a sequence number -- ticket // As a practical concern the ticket value is temporally unique // The ticket also identifies and selects a slot auto tkt = AtomicFetchIncrement (&PutCursor, 1) slot * s = &Slots[tkt & Mask] // waiting phase : // wait for slot's generation to match the tkt value assigned to this put() invocation. // The "generation" is implicitly encoded as the upper bits in the cursor // above those used to specify the index : tkt div (Mask+1) // The generation serves as an epoch number to identify a cohort of threads // accessing disjoint slots while s-Turn != tkt : Pause assert s-MailBox == null s-MailBox = v // deposit and pass message Take() : // consumer : partial method - waits as necessary auto tkt = AtomicFetchIncrement (&TakeCursor,1) slot * s = &Slots[tkt & Mask] // 2-stage waiting : // First wait for turn for our generation // Acquire exclusive "take" access to slot's MailBox field // Then wait for the slot to become occupied while s-Turn != tkt : Pause // Concurrency in this section of code is now reduced to just 1 producer thread // vs 1 consumer thread. // For a given queue and slot, there will be most one Take() operation running // in this section. // Consumer waits for producer to arrive and make slot non-empty // Extract message; clear mailbox; advance Turn indicator // We have an obvious happens-before relation : // Put(m) happens-before corresponding Take() that returns that same "m" for T v = s-MailBox if v != null : s-MailBox = null ST-ST barrier s-Turn = tkt + Mask + 1 // unlock slot to admit next producer and consumer return v Pause tryTake() : // total method - returns ASAP with failure indication for auto tkt = TakeCursor slot * s = &Slots[tkt & Mask] if s-Turn != tkt : return null T v = s-MailBox // presumptive return value if v == null : return null // ratify tkt and v values and commit by advancing cursor if CAS (&TakeCursor, tkt, tkt+1) != tkt : continue s-MailBox = null ST-ST barrier s-Turn = tkt + Mask + 1 return v The basic idea derives from the Partitioned Ticket Lock "PTL" (US20120240126-A1) and the MultiLane Concurrent Bag (US8689237). The latter is essentially a circular ring-buffer where the elements themselves are queues or concurrent collections. You can think of the PTLQueue as a partitioned ticket lock "PTL" augmented to pass values from lock to unlock via the slots. Alternatively, you could conceptualize of PTLQueue as a degenerate MultiLane bag where each slot or "lane" consists of a simple single-word MailBox instead of a general queue. Each lane in PTLQueue also has a private Turn field which acts like the Turn (Grant) variables found in PTL. Turn enforces strict FIFO ordering and restricts concurrency on the slot mailbox field to at most one simultaneous put() and take() operation. PTL uses a single "ticket" variable and per-slot Turn (grant) fields while MultiLane has distinct PutCursor and TakeCursor cursors and abstract per-slot sub-queues. Both PTL and MultiLane advance their cursor and ticket variables with atomic fetch-and-increment. PTLQueue borrows from both PTL and MultiLane and has distinct put and take cursors and per-slot Turn fields. Instead of a per-slot queues, PTLQueue uses a simple single-word MailBox field. PutCursor and TakeCursor act like a pair of ticket locks, conferring "put" and "take" access to a given slot. PutCursor, for instance, assigns an incoming put() request to a slot and serves as a PTL "Ticket" to acquire "put" permission to that slot's MailBox field. To better explain the operation of PTLQueue we deconstruct the operation of put() and take() as follows. Put() first increments PutCursor obtaining a new unique ticket. That ticket value also identifies a slot. Put() next waits for that slot's Turn field to match that ticket value. This is tantamount to using a PTL to acquire "put" permission on the slot's MailBox field. Finally, having obtained exclusive "put" permission on the slot, put() stores the message value into the slot's MailBox. Take() similarly advances TakeCursor, identifying a slot, and then acquires and secures "take" permission on a slot by waiting for Turn. Take() then waits for the slot's MailBox to become non-empty, extracts the message, and clears MailBox. Finally, take() advances the slot's Turn field, which releases both "put" and "take" access to the slot's MailBox. Note the asymmetry : put() acquires "put" access to the slot, but take() releases that lock. At any given time, for a given slot in a PTLQueue, at most one thread has "put" access and at most one thread has "take" access. This restricts concurrency from general MPMC to 1-vs-1. We have 2 ticket locks -- one for put() and one for take() -- each with its own "ticket" variable in the form of the corresponding cursor, but they share a single "Grant" egress variable in the form of the slot's Turn variable. Advancing the PutCursor, for instance, serves two purposes. First, we obtain a unique ticket which identifies a slot. Second, incrementing the cursor is the doorway protocol step to acquire the per-slot mutual exclusion "put" lock. The cursors and operations to increment those cursors serve double-duty : slot-selection and ticket assignment for locking the slot's MailBox field. At any given time a slot MailBox field can be in one of the following states: empty with no pending operations -- neutral state; empty with one or more waiting take() operations pending -- deficit; occupied with no pending operations; occupied with one or more waiting put() operations -- surplus; empty with a pending put() or pending put() and take() operations -- transitional; or occupied with a pending take() or pending put() and take() operations -- transitional. The partial put() and take() operators can be implemented with an atomic fetch-and-increment operation, which may confer a performance advantage over a CAS-based loop. In addition we have independent PutCursor and TakeCursor cursors. Critically, a put() operation modifies PutCursor but does not access the TakeCursor and a take() operation modifies the TakeCursor cursor but does not access the PutCursor. This acts to reduce coherence traffic relative to some other queue designs. It's worth noting that slow threads or obstruction in one slot (or "lane") does not impede or obstruct operations in other slots -- this gives us some degree of obstruction isolation. PTLQueue is not lock-free, however. The implementation above is expressed with polite busy-waiting (Pause) but it's trivial to implement per-slot parking and unparking to deschedule waiting threads. It's also easy to convert the queue to a more general deque by replacing the PutCursor and TakeCursor cursors with Left/Front and Right/Back cursors that can move either direction. Specifically, to push and pop from the "left" side of the deque we would decrement and increment the Left cursor, respectively, and to push and pop from the "right" side of the deque we would increment and decrement the Right cursor, respectively. We used a variation of PTLQueue for message passing in our recent OPODIS 2013 paper. ul { list-style:none; padding-left:0; padding:0; margin:0; margin-left:0; } ul#myTagID { padding: 0px; margin: 0px; list-style:none; margin-left:0;} -- -- There's quite a bit of related literature in this area. I'll call out a few relevant references: Wilson's NYU Courant Institute UltraComputer dissertation from 1988 is classic and the canonical starting point : Operating System Data Structures for Shared-Memory MIMD Machines with Fetch-and-Add. Regarding provenance and priority, I think PTLQueue or queues effectively equivalent to PTLQueue have been independently rediscovered a number of times. See CB-Queue and BNPBV, below, for instance. But Wilson's dissertation anticipates the basic idea and seems to predate all the others. Gottlieb et al : Basic Techniques for the Efficient Coordination of Very Large Numbers of Cooperating Sequential Processors Orozco et al : CB-Queue in Toward high-throughput algorithms on many-core architectures which appeared in TACO 2012. Meneghin et al : BNPVB family in Performance evaluation of inter-thread communication mechanisms on multicore/multithreaded architecture Dmitry Vyukov : bounded MPMC queue (highly recommended) Alex Otenko : US8607249 (highly related). John Mellor-Crummey : Concurrent queues: Practical fetch-and-phi algorithms. Technical Report 229, Department of Computer Science, University of Rochester Thomasson : FIFO Distributed Bakery Algorithm (very similar to PTLQueue). Scott and Scherer : Dual Data Structures I'll propose an optimization left as an exercise for the reader. Say we wanted to reduce memory usage by eliminating inter-slot padding. Such padding is usually "dark" memory and otherwise unused and wasted. But eliminating the padding leaves us at risk of increased false sharing. Furthermore lets say it was usually the case that the PutCursor and TakeCursor were numerically close to each other. (That's true in some use cases). We might still reduce false sharing by incrementing the cursors by some value other than 1 that is not trivially small and is coprime with the number of slots. Alternatively, we might increment the cursor by one and mask as usual, resulting in a logical index. We then use that logical index value to index into a permutation table, yielding an effective index for use in the slot array. The permutation table would be constructed so that nearby logical indices would map to more distant effective indices. (Open question: what should that permutation look like? Possibly some perversion of a Gray code or De Bruijn sequence might be suitable). As an aside, say we need to busy-wait for some condition as follows : "while C == 0 : Pause". Lets say that C is usually non-zero, so we typically don't wait. But when C happens to be 0 we'll have to spin for some period, possibly brief. We can arrange for the code to be more machine-friendly with respect to the branch predictors by transforming the loop into : "if C == 0 : for { Pause; if C != 0 : break; }". Critically, we want to restructure the loop so there's one branch that controls entry and another that controls loop exit. A concern is that your compiler or JIT might be clever enough to transform this back to "while C == 0 : Pause". You can sometimes avoid this by inserting a call to a some type of very cheap "opaque" method that the compiler can't elide or reorder. On Solaris, for instance, you could use :"if C == 0 : { gethrtime(); for { Pause; if C != 0 : break; }}". It's worth noting the obvious duality between locks and queues. If you have strict FIFO lock implementation with local spinning and succession by direct handoff such as MCS or CLH,then you can usually transform that lock into a queue. Hidden commentary and annotations - invisible : * And of course there's a well-known duality between queues and locks, but I'll leave that topic for another blog post. * Compare and contrast : PTLQ vs PTL and MultiLane * Equivalent : Turn; seq; sequence; pos; position; ticket * Put = Lock; Deposit Take = identify and reserve slot; wait; extract & clear; unlock * conceptualize : Distinct PutLock and TakeLock implemented as ticket lock or PTL Distinct arrival cursors but share per-slot "Turn" variable provides exclusive role-based access to slot's mailbox field put() acquires exclusive access to a slot for purposes of "deposit" assigns slot round-robin and then acquires deposit access rights/perms to that slot take() acquires exclusive access to slot for purposes of "withdrawal" assigns slot round-robin and then acquires withdrawal access rights/perms to that slot At any given time, only one thread can have withdrawal access to a slot at any given time, only one thread can have deposit access to a slot Permissible for T1 to have deposit access and T2 to simultaneously have withdrawal access * round-robin for the purposes of; role-based; access mode; access role mailslot; mailbox; allocate/assign/identify slot rights; permission; license; access permission; * PTL/Ticket hybrid Asymmetric usage ; owner oblivious lock-unlock pairing K-exclusion add Grant cursor pass message m from lock to unlock via Slots[] array Cursor performs 2 functions : + PTL ticket + Assigns request to slot in round-robin fashion Deconstruct protocol : explication put() : allocate slot in round-robin fashion acquire PTL for "put" access store message into slot associated with PTL index take() : Acquire PTL for "take" access // doorway step seq = fetchAdd (&Grant, 1) s = &Slots[seq & Mask] // waiting phase while s-Turn != seq : pause Extract : wait for s-mailbox to be full v = s-mailbox s-mailbox = null Release PTL for both "put" and "take" access s-Turn = seq + Mask + 1 * Slot round-robin assignment and lock "doorway" protocol leverage the same cursor and FetchAdd operation on that cursor FetchAdd (&Cursor,1) + round-robin slot assignment and dispersal + PTL/ticket lock "doorway" step waiting phase is via "Turn" field in slot * PTLQueue uses 2 cursors -- put and take. Acquire "put" access to slot via PTL-like lock Acquire "take" access to slot via PTL-like lock 2 locks : put and take -- at most one thread can access slot's mailbox Both locks use same "turn" field Like multilane : 2 cursors : put and take slot is simple 1-capacity mailbox instead of queue Borrow per-slot turn/grant from PTL Provides strict FIFO Lock slot : put-vs-put take-vs-take at most one put accesses slot at any one time at most one put accesses take at any one time reduction to 1-vs-1 instead of N-vs-M concurrency Per slot locks for put/take Release put/take by advancing turn * is instrumental in ... * P-V Semaphore vs lock vs K-exclusion * See also : FastQueues-excerpt.java dice-etc/queue-mpmc-bounded-blocking-circular-xadd/ * PTLQueue is the same as PTLQB - identical * Expedient return; ASAP; prompt; immediately * Lamport's Bakery algorithm : doorway step then waiting phase Threads arriving at doorway obtain a unique ticket number Threads enter in ticket order * In the terminology of Reed and Kanodia a ticket lock corresponds to the busy-wait implementation of a semaphore using an eventcount and a sequencer It can also be thought of as an optimization of Lamport's bakery lock was designed for fault-tolerance rather than performance Instead of spinning on the release counter, processors using a bakery lock repeatedly examine the tickets of their peers --

    Read the article

  • Collision Detection algorithms with early Collision exit

    - by Grieverheart
    I'm using collision detection in Monte Carlo simulations and at the moment I'm using GJK which is quite fast. I can't help to think it could be done even faster though. In the simulations, about 70% of the time GJK is run, it detects a collision. Thus collisions are more than non-collisions in my case. Most collision detection algorithms I know have an early non-collision exit test. Are there any collision detection algorithms that have an early collision detect instead of non-collision and could be potentially faster than GJK in case of collision?

    Read the article

  • C++ - Constructor or Initialize Method to Startup

    - by Bob Fincheimer
    I want to determine when to do non-trivial initialization of a class. I see two times to do initialization: constructor and other method. I want to figure out when to use each. Choice 1: Constructor does initialization MyClass::MyClass(Data const& data) : m_data() { // does non-trivial initialization here } MyClass::~MyClass() { // cleans up here } Choice 2: Defer initialization to an initialize method MyClass::MyClass() : m_data() {} MyClass::Initialize(Data const& data) { // does non-trivial initialization here } MyClass::~MyClass() { // cleans up here } So to try and remove any subjectivity I want to figure out which is better in a couple of situations: Class that encapsulates a resource (window/font/some sort of handle) Class that composites resources to do something (a control/domain object) Data structure classes (tree/list/etc.) [Anything else you can think of] Things to analyze: Performance Ease of use by other developers How error-prone/opportunities for bugs [Anything else you can think of]

    Read the article

< Previous Page | 91 92 93 94 95 96 97 98 99 100 101 102  | Next Page >