Search Results

Search found 32994 results on 1320 pages for 'second level cache'.

Page 374/1320 | < Previous Page | 370 371 372 373 374 375 376 377 378 379 380 381  | Next Page >

• Slow filesystem access

  - by danneh3826

  I'm trying to diagnose a slow filesystem issue on a server I look after. It's been ongoing for quite some time, and I've run out of ideas as to what I can try. Here's the thick of it. The server itself is a Dell Poweredge T310. It has 4 SAS hard drives in it, configured at RAID5, and is running Citrix XenServer 5.6. The VM is a (relatively) old Debian 5.0.6 installation. It's given 4 cores, and 4Gb's of RAM. It has 3 volumes. A 10Gb volume (ext3) for the system, 980Gb volume (xfs) for data (~94% full), and another 200Gb volume (xfs) for data (~13% full). Now here's the weird thing. Read/write access to the 980Gb volume is really slow. I might get 5Mb/s out of it if I'm lucky. At first I figured it was actually disk access in the system, or at a hypervisor level, but ruled that out entirely as other VMs on the same host are running perfectly fine (a good couple hundred Mb/s disk r/w access). So then I started to target this particular VM. I started thinking it was XFS, but to prove it I wasn't going to attempt to change the filesystem on the 980Gb drive, with years and years of billions of files on there. So I provisioned the 200Gb drive, and did the same read/write test (basically dd), and got a good couple hundred Mb/s r/w access to it. So that ruled out the VM, the hardware, and the filesystem type. There's also a lot of these in /var/log/kern.log; (sorry, this is quite long) Sep 4 10:16:59 uriel kernel: [32571790.564689] httpd: page allocation failure. order:5, mode:0x4020 Sep 4 10:16:59 uriel kernel: [32571790.564693] Pid: 7318, comm: httpd Not tainted 2.6.32-4-686-bigmem #1 Sep 4 10:16:59 uriel kernel: [32571790.564696] Call Trace: Sep 4 10:16:59 uriel kernel: [32571790.564705] [<c1092a4d>] ? __alloc_pages_nodemask+0x476/0x4e0 Sep 4 10:16:59 uriel kernel: [32571790.564711] [<c1092ac3>] ? __get_free_pages+0xc/0x17 Sep 4 10:16:59 uriel kernel: [32571790.564716] [<c10b632e>] ? __kmalloc+0x30/0x128 Sep 4 10:16:59 uriel kernel: [32571790.564722] [<c11dd774>] ? pskb_expand_head+0x4f/0x157 Sep 4 10:16:59 uriel kernel: [32571790.564727] [<c11ddbbf>] ? __pskb_pull_tail+0x41/0x1fb Sep 4 10:16:59 uriel kernel: [32571790.564732] [<c11e4882>] ? dev_queue_xmit+0xe4/0x38e Sep 4 10:16:59 uriel kernel: [32571790.564738] [<c1205902>] ? ip_finish_output+0x0/0x5c Sep 4 10:16:59 uriel kernel: [32571790.564742] [<c12058c7>] ? ip_finish_output2+0x187/0x1c2 Sep 4 10:16:59 uriel kernel: [32571790.564747] [<c1204dc8>] ? ip_local_out+0x15/0x17 Sep 4 10:16:59 uriel kernel: [32571790.564751] [<c12055a9>] ? ip_queue_xmit+0x31e/0x379 Sep 4 10:16:59 uriel kernel: [32571790.564758] [<c1279a90>] ? _spin_lock_bh+0x8/0x1e Sep 4 10:16:59 uriel kernel: [32571790.564767] [<eda15a8d>] ? __nf_ct_refresh_acct+0x66/0xa4 [nf_conntrack] Sep 4 10:16:59 uriel kernel: [32571790.564773] [<c103bf42>] ? _local_bh_enable_ip+0x16/0x6e Sep 4 10:16:59 uriel kernel: [32571790.564779] [<c1214593>] ? tcp_transmit_skb+0x595/0x5cc Sep 4 10:16:59 uriel kernel: [32571790.564785] [<c1005c4f>] ? xen_restore_fl_direct_end+0x0/0x1 Sep 4 10:16:59 uriel kernel: [32571790.564791] [<c12165ea>] ? tcp_write_xmit+0x7a3/0x874 Sep 4 10:16:59 uriel kernel: [32571790.564796] [<c121203a>] ? tcp_ack+0x1611/0x1802 Sep 4 10:16:59 uriel kernel: [32571790.564801] [<c10055ec>] ? xen_force_evtchn_callback+0xc/0x10 Sep 4 10:16:59 uriel kernel: [32571790.564806] [<c121392f>] ? tcp_established_options+0x1d/0x8b Sep 4 10:16:59 uriel kernel: [32571790.564811] [<c1213be4>] ? tcp_current_mss+0x38/0x53 Sep 4 10:16:59 uriel kernel: [32571790.564816] [<c1216701>] ? __tcp_push_pending_frames+0x1e/0x50 Sep 4 10:16:59 uriel kernel: [32571790.564821] [<c1212246>] ? tcp_data_snd_check+0x1b/0xd2 Sep 4 10:16:59 uriel kernel: [32571790.564825] [<c1212de3>] ? tcp_rcv_established+0x5d0/0x626 Sep 4 10:16:59 uriel kernel: [32571790.564831] [<c121902c>] ? tcp_v4_do_rcv+0x15f/0x2cf Sep 4 10:16:59 uriel kernel: [32571790.564835] [<c1219561>] ? tcp_v4_rcv+0x3c5/0x5c0 Sep 4 10:16:59 uriel kernel: [32571790.564841] [<c120197e>] ? ip_local_deliver_finish+0x10c/0x18c Sep 4 10:16:59 uriel kernel: [32571790.564846] [<c12015a4>] ? ip_rcv_finish+0x2c4/0x2d8 Sep 4 10:16:59 uriel kernel: [32571790.564852] [<c11e3b71>] ? netif_receive_skb+0x3bb/0x3d6 Sep 4 10:16:59 uriel kernel: [32571790.564864] [<ed823efc>] ? xennet_poll+0x9b8/0xafc [xen_netfront] Sep 4 10:16:59 uriel kernel: [32571790.564869] [<c11e40ee>] ? net_rx_action+0x96/0x194 Sep 4 10:16:59 uriel kernel: [32571790.564874] [<c103bd4c>] ? __do_softirq+0xaa/0x151 Sep 4 10:16:59 uriel kernel: [32571790.564878] [<c103be24>] ? do_softirq+0x31/0x3c Sep 4 10:16:59 uriel kernel: [32571790.564883] [<c103befa>] ? irq_exit+0x26/0x58 Sep 4 10:16:59 uriel kernel: [32571790.564890] [<c118ff9f>] ? xen_evtchn_do_upcall+0x12c/0x13e Sep 4 10:16:59 uriel kernel: [32571790.564896] [<c1008c3f>] ? xen_do_upcall+0x7/0xc Sep 4 10:16:59 uriel kernel: [32571790.564899] Mem-Info: Sep 4 10:16:59 uriel kernel: [32571790.564902] DMA per-cpu: Sep 4 10:16:59 uriel kernel: [32571790.564905] CPU 0: hi: 0, btch: 1 usd: 0 Sep 4 10:16:59 uriel kernel: [32571790.564908] CPU 1: hi: 0, btch: 1 usd: 0 Sep 4 10:16:59 uriel kernel: [32571790.564911] CPU 2: hi: 0, btch: 1 usd: 0 Sep 4 10:16:59 uriel kernel: [32571790.564914] CPU 3: hi: 0, btch: 1 usd: 0 Sep 4 10:16:59 uriel kernel: [32571790.564916] Normal per-cpu: Sep 4 10:16:59 uriel kernel: [32571790.564919] CPU 0: hi: 186, btch: 31 usd: 175 Sep 4 10:16:59 uriel kernel: [32571790.564922] CPU 1: hi: 186, btch: 31 usd: 165 Sep 4 10:16:59 uriel kernel: [32571790.564925] CPU 2: hi: 186, btch: 31 usd: 30 Sep 4 10:16:59 uriel kernel: [32571790.564928] CPU 3: hi: 186, btch: 31 usd: 140 Sep 4 10:16:59 uriel kernel: [32571790.564931] HighMem per-cpu: Sep 4 10:16:59 uriel kernel: [32571790.564933] CPU 0: hi: 186, btch: 31 usd: 159 Sep 4 10:16:59 uriel kernel: [32571790.564936] CPU 1: hi: 186, btch: 31 usd: 22 Sep 4 10:16:59 uriel kernel: [32571790.564939] CPU 2: hi: 186, btch: 31 usd: 24 Sep 4 10:16:59 uriel kernel: [32571790.564942] CPU 3: hi: 186, btch: 31 usd: 13 Sep 4 10:16:59 uriel kernel: [32571790.564947] active_anon:485974 inactive_anon:121138 isolated_anon:0 Sep 4 10:16:59 uriel kernel: [32571790.564948] active_file:75215 inactive_file:79510 isolated_file:0 Sep 4 10:16:59 uriel kernel: [32571790.564949] unevictable:0 dirty:516 writeback:15 unstable:0 Sep 4 10:16:59 uriel kernel: [32571790.564950] free:230770 slab_reclaimable:36661 slab_unreclaimable:21249 Sep 4 10:16:59 uriel kernel: [32571790.564952] mapped:20016 shmem:29450 pagetables:5600 bounce:0 Sep 4 10:16:59 uriel kernel: [32571790.564958] DMA free:2884kB min:72kB low:88kB high:108kB active_anon:0kB inactive_anon:0kB active_file:5692kB inactive_file:724kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:15872kB mlocked:0kB dirty:8kB writeback:0kB mapped:0kB shmem:0kB slab_reclaimable:5112kB slab_unreclaimable:156kB kernel_stack:56kB pagetables:0kB unstable:0kB bounce:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? no Sep 4 10:16:59 uriel kernel: [32571790.564964] lowmem_reserve[]: 0 698 4143 4143 Sep 4 10:16:59 uriel kernel: [32571790.564977] Normal free:143468kB min:3344kB low:4180kB high:5016kB active_anon:56kB inactive_anon:2068kB active_file:131812kB inactive_file:131728kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:715256kB mlocked:0kB dirty:156kB writeback:0kB mapped:308kB shmem:4kB slab_reclaimable:141532kB slab_unreclaimable:84840kB kernel_stack:1928kB pagetables:22400kB unstable:0kB bounce:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? no Sep 4 10:16:59 uriel kernel: [32571790.564983] lowmem_reserve[]: 0 0 27559 27559 Sep 4 10:16:59 uriel kernel: [32571790.564995] HighMem free:776728kB min:512kB low:4636kB high:8760kB active_anon:1943840kB inactive_anon:482484kB active_file:163356kB inactive_file:185588kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:3527556kB mlocked:0kB dirty:1900kB writeback:60kB mapped:79756kB shmem:117796kB slab_reclaimable:0kB slab_unreclaimable:0kB kernel_stack:0kB pagetables:0kB unstable:0kB bounce:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? no Sep 4 10:16:59 uriel kernel: [32571790.565001] lowmem_reserve[]: 0 0 0 0 Sep 4 10:16:59 uriel kernel: [32571790.565011] DMA: 385*4kB 16*8kB 3*16kB 9*32kB 6*64kB 2*128kB 1*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 2900kB Sep 4 10:16:59 uriel kernel: [32571790.565032] Normal: 21505*4kB 6508*8kB 273*16kB 24*32kB 3*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 143412kB Sep 4 10:16:59 uriel kernel: [32571790.565054] HighMem: 949*4kB 8859*8kB 7063*16kB 6186*32kB 4631*64kB 727*128kB 6*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 776604kB Sep 4 10:16:59 uriel kernel: [32571790.565076] 198980 total pagecache pages Sep 4 10:16:59 uriel kernel: [32571790.565079] 14850 pages in swap cache Sep 4 10:16:59 uriel kernel: [32571790.565082] Swap cache stats: add 2556273, delete 2541423, find 82961339/83153719 Sep 4 10:16:59 uriel kernel: [32571790.565085] Free swap = 250592kB Sep 4 10:16:59 uriel kernel: [32571790.565087] Total swap = 385520kB Sep 4 10:16:59 uriel kernel: [32571790.575454] 1073152 pages RAM Sep 4 10:16:59 uriel kernel: [32571790.575458] 888834 pages HighMem Sep 4 10:16:59 uriel kernel: [32571790.575461] 11344 pages reserved Sep 4 10:16:59 uriel kernel: [32571790.575463] 1090481 pages shared Sep 4 10:16:59 uriel kernel: [32571790.575465] 737188 pages non-shared Now, I've no idea what this means. There's plenty of free memory; total used free shared buffers cached Mem: 4247232 3455904 791328 0 5348 736412 -/+ buffers/cache: 2714144 1533088 Swap: 385520 131004 254516 Though now I see the swap is relatively low in size, but would that matter? I've been starting to think about fragmentation, or inode usage on that large partition, but a recent fsck on it showed is as only like 0.5% fragmented. Which leaves me with inode usage, but how much of an effect really would a large inode table or filesystem TOC have? I've love to hear people's opinions on this. It's driving me potty! df -h output; Filesystem Size Used Avail Use% Mounted on /dev/xvda1 9.5G 6.6G 2.4G 74% / tmpfs 2.1G 0 2.1G 0% /lib/init/rw udev 10M 520K 9.5M 6% /dev tmpfs 2.1G 0 2.1G 0% /dev/shm /dev/xvdb 980G 921G 59G 94% /data

  Read the article

• How to implement a genetic algorithm with distance, time, and cost

  - by ari

  I want to make a solution to find the optimum route of school visit. For example, I want to visit 5 schools (A, B, C, D, E) in my city. Then I must find out what school I should visit first, then the second, then the third etc. with distance, time, and cost criteria. The problem is, I am confused about how to use distance with time and cost (fuel usage) estimation in genetic algorithm to find the optimum route?

  Read the article

• OpenStack: Keystone service stops immediately after starting

  - by user241618

  When restarting the Keystone service, it starts with a PID but within a fraction of second it stops. Checking the status immediately afterwards, it shows a different PID and when rechecking afterwards, it's dead. root@hyper5:~# service keystone restart stop: Unknown instance: keystone start/running, process 37746 root@hyper5:~# service keystone status keystone start/running, process 37750 root@hyper5:~# service keystone status keystone stop/waiting

  Read the article

• Use IIS Application Initialization for keeping ASP.NET Apps alive

  - by Rick Strahl

  I've been working quite a bit with Windows Services in the recent months, and well, it turns out that Windows Services are quite a bear to debug, deploy, update and maintain. The process of getting services set up,  debugged and updated is a major chore that has to be extensively documented and or automated specifically. On most projects when a service is built, people end up scrambling for the right 'process' to use for administration. Web app deployment and maintenance on the other hand are common and well understood today, as we are constantly dealing with Web apps. There's plenty of infrastructure and tooling built into Web Tools like Visual Studio to facilitate the process. By comparison Windows Services or anything self-hosted for that matter seems convoluted.In fact, in a recent blog post I mentioned that on a recent project I'd been using self-hosting for SignalR inside of a Windows service, because the application is in fact a 'service' that also needs to send out lots of messages via SignalR. But the reality is that it could just as well be an IIS application with a service component that runs in the background. Either way you look at it, it's either a Windows Service with a built in Web Server, or an IIS application running a Service application, neither of which follows the standard Service or Web App template.Personally I much prefer Web applications. Running inside of IIS I get all the benefits of the IIS platform including service lifetime management (crash and restart), controlled shutdowns, the whole security infrastructure including easy certificate support, hot-swapping of code and the the ability to publish directly to IIS from within Visual Studio with ease.Because of these benefits we set out to move from the self hosted service into an ASP.NET Web app instead.The Missing Link for ASP.NET as a Service: Auto-LoadingI've had moments in the past where I wanted to run a 'service like' application in ASP.NET because when you think about it, it's so much easier to control a Web application remotely. Services are locked into start/stop operations, but if you host inside of a Web app you can write your own ticket and control it from anywhere. In fact nearly 10 years ago I built a background scheduling application that ran inside of ASP.NET and it worked great and it's still running doing its job today.The tricky part for running an app as a service inside of IIS then and now, is how to get IIS and ASP.NET launched so your 'service' stays alive even after an Application Pool reset. 7 years ago I faked it by using a web monitor (my own West Wind Web Monitor app) I was running anyway to monitor my various web sites for uptime, and having the monitor ping my 'service' every 20 seconds to effectively keep ASP.NET alive or fire it back up after a reload. I used a simple scheduler class that also includes some logic for 'self-reloading'. Hacky for sure, but it worked reliably.Luckily today it's much easier and more integrated to get IIS to launch ASP.NET as soon as an Application Pool is started by using the Application Initialization Module. The Application Initialization Module basically allows you to turn on Preloading on the Application Pool and the Site/IIS App, which essentially fires a request through the IIS pipeline as soon as the Application Pool has been launched. This means that effectively your ASP.NET app becomes active immediately, Application_Start is fired making sure your app stays up and running at all times. All the other features like Application Pool recycling and auto-shutdown after idle time still work, but IIS will then always immediately re-launch the application.Getting started with Application InitializationAs of IIS 8 Application Initialization is part of the IIS feature set. For IIS 7 and 7.5 there's a separate download available via Web Platform Installer. Using IIS 8 Application Initialization is an optional install component in Windows or the Windows Server Role Manager: This is an optional component so make sure you explicitly select it.IIS Configuration for Application InitializationInitialization needs to be applied on the Application Pool as well as the IIS Application level. As of IIS 8 these settings can be made through the IIS Administration console.Start with the Application Pool:Here you need to set both the Start Automatically which is always set, and the StartMode which should be set to AlwaysRunning. Both have to be set - the Start Automatically flag is set true by default and controls the starting of the application pool itself while Always Running flag is required in order to launch the application. Without the latter flag set the site settings have no effect.Now on the Site/Application level you can specify whether the site should pre load: Set the Preload Enabled flag to true.At this point ASP.NET apps should auto-load. This is all that's needed to pre-load the site if all you want is to get your site launched automatically.If you want a little more control over the load process you can add a few more settings to your web.config file that allow you to show a static page while the App is starting up. This can be useful if startup is really slow, so rather than displaying blank screen while the user is fiddling their thumbs you can display a static HTML page instead: <system.webServer> <applicationInitialization remapManagedRequestsTo="Startup.htm" skipManagedModules="true"> <add initializationPage="ping.ashx" /> </applicationInitialization> </system.webServer>This allows you to specify a page to execute in a dry run. IIS basically fakes request and pushes it directly into the IIS pipeline without hitting the network. You specify a page and IIS will fake a request to that page in this case ping.ashx which just returns a simple OK string - ie. a fast pipeline request. This request is run immediately after Application Pool restart, and while this request is running and your app is warming up, IIS can display an alternate static page - Startup.htm above. So instead of showing users an empty loading page when clicking a link on your site you can optionally show some sort of static status page that says, "we'll be right back".  I'm not sure if that's such a brilliant idea since this can be pretty disruptive in some cases. Personally I think I prefer letting people wait, but at least get the response they were supposed to get back rather than a random page. But it's there if you need it.Note that the web.config stuff is optional. If you don't provide it IIS hits the default site link (/) and even if there's no matching request at the end of that request it'll still fire the request through the IIS pipeline. Ideally though you want to make sure that an ASP.NET endpoint is hit either with your default page, or by specify the initializationPage to ensure ASP.NET actually gets hit since it's possible for IIS fire unmanaged requests only for static pages (depending how your pipeline is configured).What about AppDomain Restarts?In addition to full Worker Process recycles at the IIS level, ASP.NET also has to deal with AppDomain shutdowns which can occur for a variety of reasons:Files are updated in the BIN folderWeb Deploy to your siteweb.config is changedHard application crashThese operations don't cause the worker process to restart, but they do cause ASP.NET to unload the current AppDomain and start up a new one. Because the features above only apply to Application Pool restarts, AppDomain restarts could also cause your 'ASP.NET service' to stop processing in the background.In order to keep the app running on AppDomain recycles, you can resort to a simple ping in the Application_End event:protected void Application_End() { var client = new WebClient(); var url = App.AdminConfiguration.MonitorHostUrl + "ping.aspx"; client.DownloadString(url); Trace.WriteLine("Application Shut Down Ping: " + url); }which fires any ASP.NET url to the current site at the very end of the pipeline shutdown which in turn ensures that the site immediately starts back up.Manual Configuration in ApplicationHost.configThe above UI corresponds to the following ApplicationHost.config settings. If you're using IIS 7, there's no UI for these flags so you'll have to manually edit them.When you install the Application Initialization component into IIS it should auto-configure the module into ApplicationHost.config. Unfortunately for me, with Mr. Murphy in his best form for me, the module registration did not occur and I had to manually add it.<globalModules> <add name="ApplicationInitializationModule" image="%windir%\System32\inetsrv\warmup.dll" /> </globalModules>Most likely you won't need ever need to add this, but if things are not working it's worth to check if the module is actually registered.Next you need to configure the ApplicationPool and the Web site. The following are the two relevant entries in ApplicationHost.config.<system.applicationHost> <applicationPools> <add name="West Wind West Wind Web Connection" autoStart="true" startMode="AlwaysRunning" managedRuntimeVersion="v4.0" managedPipelineMode="Integrated"> <processModel identityType="LocalSystem" setProfileEnvironment="true" /> </add> </applicationPools> <sites> <site name="Default Web Site" id="1"> <application path="/MPress.Workflow.WebQueueMessageManager" applicationPool="West Wind West Wind Web Connection" preloadEnabled="true"> <virtualDirectory path="/" physicalPath="C:\Clients\…" /> </application> </site> </sites> </system.applicationHost>On the Application Pool make sure to set the autoStart and startMode flags to true and AlwaysRunning respectively. On the site make sure to set the preloadEnabled flag to true.And that's all you should need. You can still set the web.config settings described above as well.ASP.NET as a Service?In the particular application I'm working on currently, we have a queue manager that runs as standalone service that polls a database queue and picks out jobs and processes them on several threads. The service can spin up any number of threads and keep these threads alive in the background while IIS is running doing its own thing. These threads are newly created threads, so they sit completely outside of the IIS thread pool. In order for this service to work all it needs is a long running reference that keeps it alive for the life time of the application.In this particular app there are two components that run in the background on their own threads: A scheduler that runs various scheduled tasks and handles things like picking up emails to send out outside of IIS's scope and the QueueManager. Here's what this looks like in global.asax:public class Global : System.Web.HttpApplication { private static ApplicationScheduler scheduler; private static ServiceLauncher launcher; protected void Application_Start(object sender, EventArgs e) { // Pings the service and ensures it stays alive scheduler = new ApplicationScheduler() { CheckFrequency = 600000 }; scheduler.Start(); launcher = new ServiceLauncher(); launcher.Start(); // register so shutdown is controlled HostingEnvironment.RegisterObject(launcher); }}By keeping these objects around as static instances that are set only once on startup, they survive the lifetime of the application. The code in these classes is essentially unchanged from the Windows Service code except that I could remove the various overrides required for the Windows Service interface (OnStart,OnStop,OnResume etc.). Otherwise the behavior and operation is very similar.In this application ASP.NET serves two purposes: It acts as the host for SignalR and provides the administration interface which allows remote management of the 'service'. I can start and stop the service remotely by shutting down the ApplicationScheduler very easily. I can also very easily feed stats from the queue out directly via a couple of Web requests or (as we do now) through the SignalR service.Registering a Background Object with ASP.NETNotice also the use of the HostingEnvironment.RegisterObject(). This function registers an object with ASP.NET to let it know that it's a background task that should be notified if the AppDomain shuts down. RegisterObject() requires an interface with a Stop() method that's fired and allows your code to respond to a shutdown request. Here's what the IRegisteredObject::Stop() method looks like on the launcher:public void Stop(bool immediate = false) { LogManager.Current.LogInfo("QueueManager Controller Stopped."); Controller.StopProcessing(); Controller.Dispose(); Thread.Sleep(1500); // give background threads some time HostingEnvironment.UnregisterObject(this); }Implementing IRegisterObject should help with reliability on AppDomain shutdowns. Thanks to Justin Van Patten for pointing this out to me on Twitter.RegisterObject() is not required but I would highly recommend implementing it on whatever object controls your background processing to all clean shutdowns when the AppDomain shuts down.Testing it outI'm still in the testing phase with this particular service to see if there are any side effects. But so far it doesn't look like it. With about 50 lines of code I was able to replace the Windows service startup to Web start up - everything else just worked as is. An honorable mention goes to SignalR 2.0's oWin hosting, because with the new oWin based hosting no code changes at all were required, merely a couple of configuration file settings and an assembly directive needed, to point at the SignalR startup class. Sweet!It also seems like SignalR is noticeably faster running inside of IIS compared to self-host. Startup feels faster because of the preload.Starting and Stopping the 'Service'Because the application is running as a Web Server, it's easy to have a Web interface for starting and stopping the services running inside of the service. For our queue manager the SignalR service and front monitoring app has a play and stop button for toggling the queue.If you want more administrative control and have it work more like a Windows Service you can also stop the application pool explicitly from the command line which would be equivalent to stopping and restarting a service.To start and stop from the command line you can use the IIS appCmd tool. To stop:> %windir%\system32\inetsrv\appcmd stop apppool /apppool.name:"Weblog"and to start> %windir%\system32\inetsrv\appcmd start apppool /apppool.name:"Weblog"Note that when you explicitly force the AppPool to stop running either in the UI (on the ApplicationPools page use Start/Stop) or via command line tools, the application pool will not auto-restart immediately. You have to manually start it back up.What's not to like?There are certainly a lot of benefits to running a background service in IIS, but… ASP.NET applications do have more overhead in terms of memory footprint and startup time is a little slower, but generally for server applications this is not a big deal. If the application is stable the service should fire up and stay running indefinitely. A lot of times this kind of service interface can simply be attached to an existing Web application, or if scalability requires be offloaded to its own Web server.Easier to work withBut the ultimate benefit here is that it's much easier to work with a Web app as opposed to a service. While developing I can simply turn off the auto-launch features and launch the service on demand through IIS simply by hitting a page on the site. If I want to shut down an IISRESET -stop will shut down the service easily enough. I can then attach a debugger anywhere I want and this works like any other ASP.NET application. Yes you end up on a background thread for debugging but Visual Studio handles that just fine and if you stay on a single thread this is no different than debugging any other code.SummaryUsing ASP.NET to run background service operations is probably not a super common scenario, but it probably should be something that is considered carefully when building services. Many applications have service like features and with the auto-start functionality of the Application Initialization module, it's easy to build this functionality into ASP.NET. Especially when combined with the notification features of SignalR it becomes very, very easy to create rich services that can also communicate their status easily to the outside world.Whether it's existing applications that need some background processing for scheduling related tasks, or whether you just create a separate site altogether just to host your service it's easy to do and you can leverage the same tool chain you're already using for other Web projects. If you have lots of service projects it's worth considering… give it some thought…© Rick Strahl, West Wind Technologies, 2005-2013Posted in ASP.NET  SignalR  IIS   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

  Read the article

• Upgrade Exchange 2003 to Exchange 2010 – Part II

  In Jaap's second article on upgrading straight from Exchange Server 2003 to 2010, he explains how to move the various services from Exchange Server 2003 to Exchange Server 2010 and fully decommission the Exchange Server 2003 servers.

  Read the article

• Setting up a Reverse Proxy using IIS, URL Rewrite and ARR

  - by The Official Microsoft IIS Site

  Today there was a question in the IIS.net Forums asking how to expose two different Internet sites from another site making them look like if they were subdirectories in the main site. So for example the goal was to have a site: www.site.com expose a www.site.com/company1 and a www.site.com/company2 and have the content from “www.company1.com” served for the first one and “www.company2.com” served in the second one. Furthermore we would like to have the responses cached in the server for performance...(read more)

  Read the article

• Box Selection and Multi-Line Editing with VS 2010

  - by Latest Microsoft Blogs

  This is the twenty-second in a series of blog posts I’m doing on the VS 2010 and .NET 4 release. I’ve already covered some of the code editor improvements in the VS 2010 release.  In particular, I’ve blogged about the Code Intellisense Improvements Read More......(read more)

  Read the article

• The right way of using index.html

  - by Jeyekomon

  I have quite a lot of issues I'd like to hear your opinion on, so I hope I'll manage to explain it well enough. I should also note that I'm beginner equipped only with the knowledge of HTML and CSS so although I'm almost sure that there is a simple solution using powerful PHP, it won't help me. Let's say that I have my personal blog on the address example.com/blog.html and there are links to several sub-blogs example.com/blog/math.html, example.com/blog/coding.html etc. So my root folder contains blog.html and blog folder, the blog folder itself contains files math.html and coding.html. First of all, I learned (from Google Webmasters Tools) that for SEO and aesthetical purposes it's good to unify example.com.com and example.com/index.html by adding _rel="canonical"_ attribute into the source of the index.html. Using a couple of other tricks (like linking to ../ and ./) I got rid of the ugly index.html appearing in my web addresses. And now I wonder if this trick can be used not only for the root folder but for any folder? I mean, I would move my blog.html into the blog folder, rename it into the index.html and add rel="canonical" to unify example.com/blog/index.html with example.com/blog/. This trick would change the address of my blog from example.com/blog.html into example.com/blog/. Not finished! I'm also experiencing problems with the google robot indexing my folders. So when I type site:example.com/ into the google search, the link to my folder example.com/blog/ with raw files, icons etc. appears among the other results. I guess there are also other ways how to fix it, but IMHO the change mentioned above would do the trick too - the index.html in the blog folder would preserve the user from viewing the actual raw content of that folder, there would appear only the right link example.com/blog/ in the google search and (I hope that) _rel="canonical"_ would make the second, unwanted link example.com/blog/index.html not to appear in the search results. So my questions are: Is it a good practice to have the index.html file in every subfolder or is it intended to be only in the root folder? Are there any disadvantages or problems that may occur when using the second, "index in every folder" method? Which one of the two ways of structuring the website described above would you prefer?

  Read the article

• C#/.NET Little Wonders: The Concurrent Collections (1 of 3)

  - by James Michael Hare

  Once again we consider some of the lesser known classes and keywords of C#.  In the next few weeks, we will discuss the concurrent collections and how they have changed the face of concurrent programming. This week’s post will begin with a general introduction and discuss the ConcurrentStack<T> and ConcurrentQueue<T>.  Then in the following post we’ll discuss the ConcurrentDictionary<T> and ConcurrentBag<T>.  Finally, we shall close on the third post with a discussion of the BlockingCollection<T>. For more of the "Little Wonders" posts, see the index here. A brief history of collections In the beginning was the .NET 1.0 Framework.  And out of this framework emerged the System.Collections namespace, and it was good.  It contained all the basic things a growing programming language needs like the ArrayList and Hashtable collections.  The main problem, of course, with these original collections is that they held items of type object which means you had to be disciplined enough to use them correctly or you could end up with runtime errors if you got an object of a type you weren't expecting. Then came .NET 2.0 and generics and our world changed forever!  With generics the C# language finally got an equivalent of the very powerful C++ templates.  As such, the System.Collections.Generic was born and we got type-safe versions of all are favorite collections.  The List<T> succeeded the ArrayList and the Dictionary<TKey,TValue> succeeded the Hashtable and so on.  The new versions of the library were not only safer because they checked types at compile-time, in many cases they were more performant as well.  So much so that it's Microsoft's recommendation that the System.Collections original collections only be used for backwards compatibility. So we as developers came to know and love the generic collections and took them into our hearts and embraced them.  The problem is, thread safety in both the original collections and the generic collections can be problematic, for very different reasons. Now, if you are only doing single-threaded development you may not care – after all, no locking is required.  Even if you do have multiple threads, if a collection is “load-once, read-many” you don’t need to do anything to protect that container from multi-threaded access, as illustrated below: 1: public static class OrderTypeTranslator 2: { 3: // because this dictionary is loaded once before it is ever accessed, we don't need to synchronize 4: // multi-threaded read access 5: private static readonly Dictionary<string, char> _translator = new Dictionary<string, char> 6: { 7: {"New", 'N'}, 8: {"Update", 'U'}, 9: {"Cancel", 'X'} 10: }; 11:  12: // the only public interface into the dictionary is for reading, so inherently thread-safe 13: public static char? Translate(string orderType) 14: { 15: char charValue; 16: if (_translator.TryGetValue(orderType, out charValue)) 17: { 18: return charValue; 19: } 20:  21: return null; 22: } 23: } Unfortunately, most of our computer science problems cannot get by with just single-threaded applications or with multi-threading in a load-once manner.  Looking at  today's trends, it's clear to see that computers are not so much getting faster because of faster processor speeds -- we've nearly reached the limits we can push through with today's technologies -- but more because we're adding more cores to the boxes.  With this new hardware paradigm, it is even more important to use multi-threaded applications to take full advantage of parallel processing to achieve higher application speeds. So let's look at how to use collections in a thread-safe manner. Using historical collections in a concurrent fashion The early .NET collections (System.Collections) had a Synchronized() static method that could be used to wrap the early collections to make them completely thread-safe.  This paradigm was dropped in the generic collections (System.Collections.Generic) because having a synchronized wrapper resulted in atomic locks for all operations, which could prove overkill in many multithreading situations.  Thus the paradigm shifted to having the user of the collection specify their own locking, usually with an external object: 1: public class OrderAggregator 2: { 3: private static readonly Dictionary<string, List<Order>> _orders = new Dictionary<string, List<Order>>(); 4: private static readonly _orderLock = new object(); 5:  6: public void Add(string accountNumber, Order newOrder) 7: { 8: List<Order> ordersForAccount; 9:  10: // a complex operation like this should all be protected 11: lock (_orderLock) 12: { 13: if (!_orders.TryGetValue(accountNumber, out ordersForAccount)) 14: { 15: _orders.Add(accountNumber, ordersForAccount = new List<Order>()); 16: } 17:  18: ordersForAccount.Add(newOrder); 19: } 20: } 21: } Notice how we’re performing several operations on the dictionary under one lock.  With the Synchronized() static methods of the early collections, you wouldn’t be able to specify this level of locking (a more macro-level).  So in the generic collections, it was decided that if a user needed synchronization, they could implement their own locking scheme instead so that they could provide synchronization as needed. The need for better concurrent access to collections Here’s the problem: it’s relatively easy to write a collection that locks itself down completely for access, but anything more complex than that can be difficult and error-prone to write, and much less to make it perform efficiently!  For example, what if you have a Dictionary that has frequent reads but in-frequent updates?  Do you want to lock down the entire Dictionary for every access?  This would be overkill and would prevent concurrent reads.  In such cases you could use something like a ReaderWriterLockSlim which allows for multiple readers in a lock, and then once a writer grabs the lock it blocks all further readers until the writer is done (in a nutshell).  This is all very complex stuff to consider. Fortunately, this is where the Concurrent Collections come in.  The Parallel Computing Platform team at Microsoft went through great pains to determine how to make a set of concurrent collections that would have the best performance characteristics for general case multi-threaded use. Now, as in all things involving threading, you should always make sure you evaluate all your container options based on the particular usage scenario and the degree of parallelism you wish to acheive. This article should not be taken to understand that these collections are always supperior to the generic collections. Each fills a particular need for a particular situation. Understanding what each container is optimized for is key to the success of your application whether it be single-threaded or multi-threaded. General points to consider with the concurrent collections The MSDN points out that the concurrent collections all support the ICollection interface. However, since the collections are already synchronized, the IsSynchronized property always returns false, and SyncRoot always returns null.  Thus you should not attempt to use these properties for synchronization purposes. Note that since the concurrent collections also may have different operations than the traditional data structures you may be used to.  Now you may ask why they did this, but it was done out of necessity to keep operations safe and atomic.  For example, in order to do a Pop() on a stack you have to know the stack is non-empty, but between the time you check the stack’s IsEmpty property and then do the Pop() another thread may have come in and made the stack empty!  This is why some of the traditional operations have been changed to make them safe for concurrent use. In addition, some properties and methods in the concurrent collections achieve concurrency by creating a snapshot of the collection, which means that some operations that were traditionally O(1) may now be O(n) in the concurrent models.  I’ll try to point these out as we talk about each collection so you can be aware of any potential performance impacts.  Finally, all the concurrent containers are safe for enumeration even while being modified, but some of the containers support this in different ways (snapshot vs. dirty iteration).  Once again I’ll highlight how thread-safe enumeration works for each collection. ConcurrentStack<T>: The thread-safe LIFO container The ConcurrentStack<T> is the thread-safe counterpart to the System.Collections.Generic.Stack<T>, which as you may remember is your standard last-in-first-out container.  If you think of algorithms that favor stack usage (for example, depth-first searches of graphs and trees) then you can see how using a thread-safe stack would be of benefit. The ConcurrentStack<T> achieves thread-safe access by using System.Threading.Interlocked operations.  This means that the multi-threaded access to the stack requires no traditional locking and is very, very fast! For the most part, the ConcurrentStack<T> behaves like it’s Stack<T> counterpart with a few differences: Pop() was removed in favor of TryPop() Returns true if an item existed and was popped and false if empty. PushRange() and TryPopRange() were added Allows you to push multiple items and pop multiple items atomically. Count takes a snapshot of the stack and then counts the items. This means it is a O(n) operation, if you just want to check for an empty stack, call IsEmpty instead which is O(1). ToArray() and GetEnumerator() both also take snapshots. This means that iteration over a stack will give you a static view at the time of the call and will not reflect updates. Pushing on a ConcurrentStack<T> works just like you’d expect except for the aforementioned PushRange() method that was added to allow you to push a range of items concurrently. 1: var stack = new ConcurrentStack<string>(); 2:  3: // adding to stack is much the same as before 4: stack.Push("First"); 5:  6: // but you can also push multiple items in one atomic operation (no interleaves) 7: stack.PushRange(new [] { "Second", "Third", "Fourth" }); For looking at the top item of the stack (without removing it) the Peek() method has been removed in favor of a TryPeek().  This is because in order to do a peek the stack must be non-empty, but between the time you check for empty and the time you execute the peek the stack contents may have changed.  Thus the TryPeek() was created to be an atomic check for empty, and then peek if not empty: 1: // to look at top item of stack without removing it, can use TryPeek. 2: // Note that there is no Peek(), this is because you need to check for empty first. TryPeek does. 3: string item; 4: if (stack.TryPeek(out item)) 5: { 6: Console.WriteLine("Top item was " + item); 7: } 8: else 9: { 10: Console.WriteLine("Stack was empty."); 11: } Finally, to remove items from the stack, we have the TryPop() for single, and TryPopRange() for multiple items.  Just like the TryPeek(), these operations replace Pop() since we need to ensure atomically that the stack is non-empty before we pop from it: 1: // to remove items, use TryPop or TryPopRange to get multiple items atomically (no interleaves) 2: if (stack.TryPop(out item)) 3: { 4: Console.WriteLine("Popped " + item); 5: } 6:  7: // TryPopRange will only pop up to the number of spaces in the array, the actual number popped is returned. 8: var poppedItems = new string[2]; 9: int numPopped = stack.TryPopRange(poppedItems); 10:  11: foreach (var theItem in poppedItems.Take(numPopped)) 12: { 13: Console.WriteLine("Popped " + theItem); 14: } Finally, note that as stated before, GetEnumerator() and ToArray() gets a snapshot of the data at the time of the call.  That means if you are enumerating the stack you will get a snapshot of the stack at the time of the call.  This is illustrated below: 1: var stack = new ConcurrentStack<string>(); 2:  3: // adding to stack is much the same as before 4: stack.Push("First"); 5:  6: var results = stack.GetEnumerator(); 7:  8: // but you can also push multiple items in one atomic operation (no interleaves) 9: stack.PushRange(new [] { "Second", "Third", "Fourth" }); 10:  11: while(results.MoveNext()) 12: { 13: Console.WriteLine("Stack only has: " + results.Current); 14: } The only item that will be printed out in the above code is "First" because the snapshot was taken before the other items were added. This may sound like an issue, but it’s really for safety and is more correct.  You don’t want to enumerate a stack and have half a view of the stack before an update and half a view of the stack after an update, after all.  In addition, note that this is still thread-safe, whereas iterating through a non-concurrent collection while updating it in the old collections would cause an exception. ConcurrentQueue<T>: The thread-safe FIFO container The ConcurrentQueue<T> is the thread-safe counterpart of the System.Collections.Generic.Queue<T> class.  The concurrent queue uses an underlying list of small arrays and lock-free System.Threading.Interlocked operations on the head and tail arrays.  Once again, this allows us to do thread-safe operations without the need for heavy locks! The ConcurrentQueue<T> (like the ConcurrentStack<T>) has some departures from the non-concurrent counterpart.  Most notably: Dequeue() was removed in favor of TryDequeue(). Returns true if an item existed and was dequeued and false if empty. Count does not take a snapshot It subtracts the head and tail index to get the count.  This results overall in a O(1) complexity which is quite good.  It’s still recommended, however, that for empty checks you call IsEmpty instead of comparing Count to zero. ToArray() and GetEnumerator() both take snapshots. This means that iteration over a queue will give you a static view at the time of the call and will not reflect updates. The Enqueue() method on the ConcurrentQueue<T> works much the same as the generic Queue<T>: 1: var queue = new ConcurrentQueue<string>(); 2:  3: // adding to queue is much the same as before 4: queue.Enqueue("First"); 5: queue.Enqueue("Second"); 6: queue.Enqueue("Third"); For front item access, the TryPeek() method must be used to attempt to see the first item if the queue.  There is no Peek() method since, as you’ll remember, we can only peek on a non-empty queue, so we must have an atomic TryPeek() that checks for empty and then returns the first item if the queue is non-empty. 1: // to look at first item in queue without removing it, can use TryPeek. 2: // Note that there is no Peek(), this is because you need to check for empty first. TryPeek does. 3: string item; 4: if (queue.TryPeek(out item)) 5: { 6: Console.WriteLine("First item was " + item); 7: } 8: else 9: { 10: Console.WriteLine("Queue was empty."); 11: } Then, to remove items you use TryDequeue().  Once again this is for the same reason we have TryPeek() and not Peek(): 1: // to remove items, use TryDequeue. If queue is empty returns false. 2: if (queue.TryDequeue(out item)) 3: { 4: Console.WriteLine("Dequeued first item " + item); 5: } Just like the concurrent stack, the ConcurrentQueue<T> takes a snapshot when you call ToArray() or GetEnumerator() which means that subsequent updates to the queue will not be seen when you iterate over the results.  Thus once again the code below will only show the first item, since the other items were added after the snapshot. 1: var queue = new ConcurrentQueue<string>(); 2:  3: // adding to queue is much the same as before 4: queue.Enqueue("First"); 5:  6: var iterator = queue.GetEnumerator(); 7:  8: queue.Enqueue("Second"); 9: queue.Enqueue("Third"); 10:  11: // only shows First 12: while (iterator.MoveNext()) 13: { 14: Console.WriteLine("Dequeued item " + iterator.Current); 15: } Using collections concurrently You’ll notice in the examples above I stuck to using single-threaded examples so as to make them deterministic and the results obvious.  Of course, if we used these collections in a truly multi-threaded way the results would be less deterministic, but would still be thread-safe and with no locking on your part required! For example, say you have an order processor that takes an IEnumerable<Order> and handles each other in a multi-threaded fashion, then groups the responses together in a concurrent collection for aggregation.  This can be done easily with the TPL’s Parallel.ForEach(): 1: public static IEnumerable<OrderResult> ProcessOrders(IEnumerable<Order> orderList) 2: { 3: var proxy = new OrderProxy(); 4: var results = new ConcurrentQueue<OrderResult>(); 5:  6: // notice that we can process all these in parallel and put the results 7: // into our concurrent collection without needing any external locking! 8: Parallel.ForEach(orderList, 9: order => 10: { 11: var result = proxy.PlaceOrder(order); 12:  13: results.Enqueue(result); 14: }); 15:  16: return results; 17: } Summary Obviously, if you do not need multi-threaded safety, you don’t need to use these collections, but when you do need multi-threaded collections these are just the ticket! The plethora of features (I always think of the movie The Three Amigos when I say plethora) built into these containers and the amazing way they acheive thread-safe access in an efficient manner is wonderful to behold. Stay tuned next week where we’ll continue our discussion with the ConcurrentBag<T> and the ConcurrentDictionary<TKey,TValue>. For some excellent information on the performance of the concurrent collections and how they perform compared to a traditional brute-force locking strategy, see this wonderful whitepaper by the Microsoft Parallel Computing Platform team here.   Tweet Technorati Tags: C#,.NET,Concurrent Collections,Collections,Multi-Threading,Little Wonders,BlackRabbitCoder,James Michael Hare

  Read the article

• SQL Server 2005 SP4 is here!

  - by AaronBertrand

  Yes, the day has finally arrived, and a couple of weeks ahead of schedule. Typically when Microsoft promises a release in Qx or Hx, the software comes on the last or second last day of that quarter or half. This year, we get an early Christmas present: SQL Server 2005 SP4. To download SP4, go to this link: http://www.microsoft.com/downloads/en/details.aspx?FamilyID=b953e84f-9307-405e-bceb-47bd345baece If you are looking for the Express versions of SP4, you can get Express, Express with Tools, and...(read more)

  Read the article

• SQL SERVER – Introduction to Adaptive ETL Tool – How adaptive is your ETL?

  - by pinaldave

  I am often reminded by the fact that BI/data warehousing infrastructure is very brittle and not very adaptive to change. There are lots of basic use cases where data needs to be frequently loaded into SQL Server or another database. What I have found is that as long as the sources and targets stay the same, SSIS or any other ETL tool for that matter does a pretty good job handling these types of scenarios. But what happens when you are faced with more challenging scenarios, where the data formats and possibly the data types of the source data are changing from customer to customer?  Let’s examine a real life situation where a health management company receives claims data from their customers in various source formats. Even though this company supplied all their customers with the same claims forms, they ended up building one-off ETL applications to process the claims for each customer. Why, you ask? Well, it turned out that the claims data from various regional hospitals they needed to process had slightly different data formats, e.g. “integer” versus “string” data field definitions.  Moreover the data itself was represented with slight nuances, e.g. “0001124” or “1124” or “0000001124” to represent a particular account number, which forced them, as I eluded above, to build new ETL processes for each customer in order to overcome the inconsistencies in the various claims forms.  As a result, they experienced a lot of redundancy in these ETL processes and recognized quickly that their system would become more difficult to maintain over time. So imagine for a moment that you could use an ETL tool that helps you abstract the data formats so that your ETL transformation process becomes more reusable. Imagine that one claims form represents a data item as a string – acc_no(varchar) – while a second claims form represents the same data item as an integer – account_no(integer). This would break your traditional ETL process as the data mappings are hard-wired.  But in a world of abstracted definitions, all you need to do is create parallel data mappings to a common data representation used within your ETL application; that is, map both external data fields to a common attribute whose name and type remain unchanged within the application. acc_no(varchar) is mapped to account_number(integer) expressor Studio first claim form schema mapping account_no(integer) is also mapped to account_number(integer) expressor Studio second claim form schema mapping All the data processing logic that follows manipulates the data as an integer value named account_number. Well, these are the kind of problems that that the expressor data integration solution automates for you.  I’ve been following them since last year and encourage you to check them out by downloading their free expressor Studio ETL software. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Business Intelligence, Pinal Dave, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: ETL, SSIS

  Read the article

• Do DBA’s not desire sleep?

  - by drsql

  Or any support people for that matter.  I constantly hear people having to support this, support that, wearing the “beeper”, etc etc.  But these people do seemingly love what they do, because I hear this on “non-essential” communications channels, like Twitter, SQL Saturday conversations, etc.  These are people who are doing what they do because they like it. I have to be honest with you though, about the second time I was awakened by a beeper with the same problem I would be outraged....(read more)

  Read the article

• Beware Sneaky Reads with Unique Indexes

  - by Paul White NZ

  A few days ago, Sandra Mueller (twitter | blog) asked a question using twitter’s #sqlhelp hash tag: “Might SQL Server retrieve (out-of-row) LOB data from a table, even if the column isn’t referenced in the query?” Leaving aside trivial cases (like selecting a computed column that does reference the LOB data), one might be tempted to say that no, SQL Server does not read data you haven’t asked for.  In general, that’s quite correct; however there are cases where SQL Server might sneakily retrieve a LOB column… Example Table Here’s a T-SQL script to create that table and populate it with 1,000 rows: CREATE TABLE dbo.LOBtest ( pk INTEGER IDENTITY NOT NULL, some_value INTEGER NULL, lob_data VARCHAR(MAX) NULL, another_column CHAR(5) NULL, CONSTRAINT [PK dbo.LOBtest pk] PRIMARY KEY CLUSTERED (pk ASC) ); GO DECLARE @Data VARCHAR(MAX); SET @Data = REPLICATE(CONVERT(VARCHAR(MAX), 'x'), 65540);   WITH Numbers (n) AS ( SELECT ROW_NUMBER() OVER (ORDER BY (SELECT 0)) FROM master.sys.columns C1, master.sys.columns C2 ) INSERT LOBtest WITH (TABLOCKX) ( some_value, lob_data ) SELECT TOP (1000) N.n, @Data FROM Numbers N WHERE N.n <= 1000; Test 1: A Simple Update Let’s run a query to subtract one from every value in the some_value column: UPDATE dbo.LOBtest WITH (TABLOCKX) SET some_value = some_value - 1; As you might expect, modifying this integer column in 1,000 rows doesn’t take very long, or use many resources.  The STATITICS IO and TIME output shows a total of 9 logical reads, and 25ms elapsed time.  The query plan is also very simple: Looking at the Clustered Index Scan, we can see that SQL Server only retrieves the pk and some_value columns during the scan: The pk column is needed by the Clustered Index Update operator to uniquely identify the row that is being changed.  The some_value column is used by the Compute Scalar to calculate the new value.  (In case you are wondering what the Top operator is for, it is used to enforce SET ROWCOUNT). Test 2: Simple Update with an Index Now let’s create a nonclustered index keyed on the some_value column, with lob_data as an included column: CREATE NONCLUSTERED INDEX [IX dbo.LOBtest some_value (lob_data)] ON dbo.LOBtest (some_value) INCLUDE ( lob_data ) WITH ( FILLFACTOR = 100, MAXDOP = 1, SORT_IN_TEMPDB = ON ); This is not a useful index for our simple update query; imagine that someone else created it for a different purpose.  Let’s run our update query again: UPDATE dbo.LOBtest WITH (TABLOCKX) SET some_value = some_value - 1; We find that it now requires 4,014 logical reads and the elapsed query time has increased to around 100ms.  The extra logical reads (4 per row) are an expected consequence of maintaining the nonclustered index. The query plan is very similar to before (click to enlarge): The Clustered Index Update operator picks up the extra work of maintaining the nonclustered index. The new Compute Scalar operators detect whether the value in the some_value column has actually been changed by the update.  SQL Server may be able to skip maintaining the nonclustered index if the value hasn’t changed (see my previous post on non-updating updates for details).  Our simple query does change the value of some_data in every row, so this optimization doesn’t add any value in this specific case. The output list of columns from the Clustered Index Scan hasn’t changed from the one shown previously: SQL Server still just reads the pk and some_data columns.  Cool. Overall then, adding the nonclustered index hasn’t had any startling effects, and the LOB column data still isn’t being read from the table.  Let’s see what happens if we make the nonclustered index unique. Test 3: Simple Update with a Unique Index Here’s the script to create a new unique index, and drop the old one: CREATE UNIQUE NONCLUSTERED INDEX [UQ dbo.LOBtest some_value (lob_data)] ON dbo.LOBtest (some_value) INCLUDE ( lob_data ) WITH ( FILLFACTOR = 100, MAXDOP = 1, SORT_IN_TEMPDB = ON ); GO DROP INDEX [IX dbo.LOBtest some_value (lob_data)] ON dbo.LOBtest; Remember that SQL Server only enforces uniqueness on index keys (the some_data column).  The lob_data column is simply stored at the leaf-level of the non-clustered index.  With that in mind, we might expect this change to make very little difference.  Let’s see: UPDATE dbo.LOBtest WITH (TABLOCKX) SET some_value = some_value - 1; Whoa!  Now look at the elapsed time and logical reads: Scan count 1, logical reads 2016, physical reads 0, read-ahead reads 0, lob logical reads 36015, lob physical reads 0, lob read-ahead reads 15992.   CPU time = 172 ms, elapsed time = 16172 ms. Even with all the data and index pages in memory, the query took over 16 seconds to update just 1,000 rows, performing over 52,000 LOB logical reads (nearly 16,000 of those using read-ahead). Why on earth is SQL Server reading LOB data in a query that only updates a single integer column? The Query Plan The query plan for test 3 looks a bit more complex than before: In fact, the bottom level is exactly the same as we saw with the non-unique index.  The top level has heaps of new stuff though, which I’ll come to in a moment. You might be expecting to find that the Clustered Index Scan is now reading the lob_data column (for some reason).  After all, we need to explain where all the LOB logical reads are coming from.  Sadly, when we look at the properties of the Clustered Index Scan, we see exactly the same as before: SQL Server is still only reading the pk and some_value columns – so what’s doing the LOB reads? Updates that Sneakily Read Data We have to go as far as the Clustered Index Update operator before we see LOB data in the output list: [Expr1020] is a bit flag added by an earlier Compute Scalar.  It is set true if the some_value column has not been changed (part of the non-updating updates optimization I mentioned earlier). The Clustered Index Update operator adds two new columns: the lob_data column, and some_value_OLD.  The some_value_OLD column, as the name suggests, is the pre-update value of the some_value column.  At this point, the clustered index has already been updated with the new value, but we haven’t touched the nonclustered index yet. An interesting observation here is that the Clustered Index Update operator can read a column into the data flow as part of its update operation.  SQL Server could have read the LOB data as part of the initial Clustered Index Scan, but that would mean carrying the data through all the operations that occur prior to the Clustered Index Update.  The server knows it will have to go back to the clustered index row to update it, so it delays reading the LOB data until then.  Sneaky! Why the LOB Data Is Needed This is all very interesting (I hope), but why is SQL Server reading the LOB data?  For that matter, why does it need to pass the pre-update value of the some_value column out of the Clustered Index Update? The answer relates to the top row of the query plan for test 3.  I’ll reproduce it here for convenience: Notice that this is a wide (per-index) update plan.  SQL Server used a narrow (per-row) update plan in test 2, where the Clustered Index Update took care of maintaining the nonclustered index too.  I’ll talk more about this difference shortly. The Split/Sort/Collapse combination is an optimization, which aims to make per-index update plans more efficient.  It does this by breaking each update into a delete/insert pair, reordering the operations, removing any redundant operations, and finally applying the net effect of all the changes to the nonclustered index. Imagine we had a unique index which currently holds three rows with the values 1, 2, and 3.  If we run a query that adds 1 to each row value, we would end up with values 2, 3, and 4.  The net effect of all the changes is the same as if we simply deleted the value 1, and added a new value 4. By applying net changes, SQL Server can also avoid false unique-key violations.  If we tried to immediately update the value 1 to a 2, it would conflict with the existing value 2 (which would soon be updated to 3 of course) and the query would fail.  You might argue that SQL Server could avoid the uniqueness violation by starting with the highest value (3) and working down.  That’s fine, but it’s not possible to generalize this logic to work with every possible update query. SQL Server has to use a wide update plan if it sees any risk of false uniqueness violations.  It’s worth noting that the logic SQL Server uses to detect whether these violations are possible has definite limits.  As a result, you will often receive a wide update plan, even when you can see that no violations are possible. Another benefit of this optimization is that it includes a sort on the index key as part of its work.  Processing the index changes in index key order promotes sequential I/O against the nonclustered index. A side-effect of all this is that the net changes might include one or more inserts.  In order to insert a new row in the index, SQL Server obviously needs all the columns – the key column and the included LOB column.  This is the reason SQL Server reads the LOB data as part of the Clustered Index Update. In addition, the some_value_OLD column is required by the Split operator (it turns updates into delete/insert pairs).  In order to generate the correct index key delete operation, it needs the old key value. The irony is that in this case the Split/Sort/Collapse optimization is anything but.  Reading all that LOB data is extremely expensive, so it is sad that the current version of SQL Server has no way to avoid it. Finally, for completeness, I should mention that the Filter operator is there to filter out the non-updating updates. Beating the Set-Based Update with a Cursor One situation where SQL Server can see that false unique-key violations aren’t possible is where it can guarantee that only one row is being updated.  Armed with this knowledge, we can write a cursor (or the WHILE-loop equivalent) that updates one row at a time, and so avoids reading the LOB data: SET NOCOUNT ON; SET STATISTICS XML, IO, TIME OFF;   DECLARE @PK INTEGER, @StartTime DATETIME; SET @StartTime = GETUTCDATE();   DECLARE curUpdate CURSOR LOCAL FORWARD_ONLY KEYSET SCROLL_LOCKS FOR SELECT L.pk FROM LOBtest L ORDER BY L.pk ASC;   OPEN curUpdate;   WHILE (1 = 1) BEGIN FETCH NEXT FROM curUpdate INTO @PK;   IF @@FETCH_STATUS = -1 BREAK; IF @@FETCH_STATUS = -2 CONTINUE;   UPDATE dbo.LOBtest SET some_value = some_value - 1 WHERE CURRENT OF curUpdate; END;   CLOSE curUpdate; DEALLOCATE curUpdate;   SELECT DATEDIFF(MILLISECOND, @StartTime, GETUTCDATE()); That completes the update in 1280 milliseconds (remember test 3 took over 16 seconds!) I used the WHERE CURRENT OF syntax there and a KEYSET cursor, just for the fun of it.  One could just as well use a WHERE clause that specified the primary key value instead. Clustered Indexes A clustered index is the ultimate index with included columns: all non-key columns are included columns in a clustered index.  Let’s re-create the test table and data with an updatable primary key, and without any non-clustered indexes: IF OBJECT_ID(N'dbo.LOBtest', N'U') IS NOT NULL DROP TABLE dbo.LOBtest; GO CREATE TABLE dbo.LOBtest ( pk INTEGER NOT NULL, some_value INTEGER NULL, lob_data VARCHAR(MAX) NULL, another_column CHAR(5) NULL, CONSTRAINT [PK dbo.LOBtest pk] PRIMARY KEY CLUSTERED (pk ASC) ); GO DECLARE @Data VARCHAR(MAX); SET @Data = REPLICATE(CONVERT(VARCHAR(MAX), 'x'), 65540);   WITH Numbers (n) AS ( SELECT ROW_NUMBER() OVER (ORDER BY (SELECT 0)) FROM master.sys.columns C1, master.sys.columns C2 ) INSERT LOBtest WITH (TABLOCKX) ( pk, some_value, lob_data ) SELECT TOP (1000) N.n, N.n, @Data FROM Numbers N WHERE N.n <= 1000; Now here’s a query to modify the cluster keys: UPDATE dbo.LOBtest SET pk = pk + 1; The query plan is: As you can see, the Split/Sort/Collapse optimization is present, and we also gain an Eager Table Spool, for Halloween protection.  In addition, SQL Server now has no choice but to read the LOB data in the Clustered Index Scan: The performance is not great, as you might expect (even though there is no non-clustered index to maintain): Table 'LOBtest'. Scan count 1, logical reads 2011, physical reads 0, read-ahead reads 0, lob logical reads 36015, lob physical reads 0, lob read-ahead reads 15992.   Table 'Worktable'. Scan count 1, logical reads 2040, physical reads 0, read-ahead reads 0, lob logical reads 34000, lob physical reads 0, lob read-ahead reads 8000.   SQL Server Execution Times: CPU time = 483 ms, elapsed time = 17884 ms. Notice how the LOB data is read twice: once from the Clustered Index Scan, and again from the work table in tempdb used by the Eager Spool. If you try the same test with a non-unique clustered index (rather than a primary key), you’ll get a much more efficient plan that just passes the cluster key (including uniqueifier) around (no LOB data or other non-key columns): A unique non-clustered index (on a heap) works well too: Both those queries complete in a few tens of milliseconds, with no LOB reads, and just a few thousand logical reads.  (In fact the heap is rather more efficient). There are lots more fun combinations to try that I don’t have space for here. Final Thoughts The behaviour shown in this post is not limited to LOB data by any means.  If the conditions are met, any unique index that has included columns can produce similar behaviour – something to bear in mind when adding large INCLUDE columns to achieve covering queries, perhaps. Paul White Email: [email protected] Twitter: @PaulWhiteNZ

  Read the article

• Tips on Migrating from AquaLogic .NET Accelerator to WebCenter WSRP Producer for .NET

  - by user647124

  This year I embarked on a journey to migrate a group of ASP.NET web applications developed to integrate with WebLogic Portal 9.2 via the AquaLogic® Interaction .NET Application Accelerator 1.0 to instead use the Oracle WebCenter WSRP Producer for .NET and integrated with WebLogic Portal 10.3.4. It has been a very winding path and this blog entry is intended to share both the lessons learned and relevant approaches that led to those learnings. Like most journeys of discovery, it was not a direct path, and there are notes to let you know when it is practical to skip a section if you are in a hurry to get from here to there. For the Curious From the perspective of necessity, this section would be better at the end. If it were there, though, it would probably be read by far fewer people, including those that are actually interested in these types of sections. Those in a hurry may skip past and be none the worst for it in dealing with the hands-on bits of performing a migration from .NET Accelerator to WSRP Producer. For others who want to talk about why they did what they did after they did it, or just want to know for themselves, enjoy. A Brief (and edited) History of the WSRP for .NET Technologies (as Relevant to the this Post) Note: This section is for those who are curious about why the migration path is not as simple as many other Oracle technologies. You can skip this section in its entirety and still be just as competent in performing a migration as if you had read it. The currently deployed architecture that was to be migrated and upgraded achieved initial integration between .NET and J2EE over the WSRP protocol through the use of The AquaLogic Interaction .NET Application Accelerator. The .NET Accelerator allowed the applications that were written in ASP.NET and deployed on a Microsoft Internet Information Server (IIS) to interact with a WebLogic Portal application deployed on a WebLogic (J2EE application) Server (both version 9.2, the state of the art at the time of its creation). At the time this architectural decision for the application was made, both the AquaLogic and WebLogic brands were owned by BEA Systems. The AquaLogic brand included products acquired by BEA through the acquisition of Plumtree, whose flagship product was a portal platform available in both J2EE and .NET versions. As part of this dual technology support an adaptor was created to facilitate the use of WSRP as a communication protocol where customers wished to integrate components from both versions of the Plumtree portal. The adapter evolved over several product generations to include a broad array of both standard and proprietary WSRP integration capabilities. Later, BEA Systems was acquired by Oracle. Over the course of several years Oracle has acquired a large number of portal applications and has taken the strategic direction to migrate users of these myriad (and formerly competitive) products to the Oracle WebCenter technology stack. As part of Oracle’s strategic technology roadmap, older portal products are being schedule for end of life, including the portal products that were part of the BEA acquisition. The .NET Accelerator has been modified over a very long period of time with features driven by users of that product and developed under three different vendors (each a direct competitor in the same solution space prior to merger). The Oracle WebCenter WSRP Producer for .NET was introduced much more recently with the key objective to specifically address the needs of the WebCenter customers developing solutions accessible through both J2EE and .NET platforms utilizing the WSRP specifications. The Oracle Product Development Team also provides these insights on the drivers for developing the WSRP Producer: ***************************************** Support for ASP.NET AJAX. Controls using the ASP.NET AJAX script manager do not function properly in the Application Accelerator for .NET. Support 2 way SSL in WLP. This was not possible with the proxy/bridge set up in the existing Application Accelerator for .NET. Allow developers to code portlets (Web Parts) using the .NET framework rather than a proprietary framework. Developers had to use the Application Accelerator for .NET plug-ins to Visual Studio to manage preferences and profile data. This is now replaced with the .NET Framework Personalization (for preferences) and Profile providers. The WSRP Producer for .NET was created as a new way of developing .NET portlets. It was never designed to be an upgrade path for the Application Accelerator for .NET. .NET developers would create new .NET portlets with the WSRP Producer for .NET and leave any existing .NET portlets running in the Application Accelerator for .NET. ***************************************** The advantage to creating a new solution for WSRP is a product that is far easier for Oracle to maintain and support which in turn improves quality, reliability and maintainability for their customers. No changes to J2EE applications consuming the WSRP portlets previously rendered by the.NET Accelerator is required to migrate from the Aqualogic WSRP solution. For some customers using the .NET Accelerator the challenge is adapting their current .NET applications to work with the WSRP Producer (or any other WSRP adapter as they are proprietary by nature). Part of this adaptation is the need to deploy the .NET applications as a child to the WSRP producer web application as root. Differences between .NET Accelerator and WSRP Producer Note: This section is for those who are curious about why the migration is not as pluggable as something such as changing security providers in WebLogic Server. You can skip this section in its entirety and still be just as competent in performing a migration as if you had read it. The basic terminology used to describe the participating applications in a WSRP environment are the same when applied to either the .NET Accelerator or the WSRP Producer: Producer and Consumer. In both cases the .NET application serves as what is referred to as a WSRP environment as the Producer. The difference lies in how the two adapters create the WSRP translation of the .NET application. The .NET Accelerator, as the name implies, is meant to serve as a quick way of adding WSRP capability to a .NET application. As such, at a high level, the .NET Accelerator behaves as a proxy for requests between the .NET application and the WSRP Consumer. A WSRP request is sent from the consumer to the .NET Accelerator, the.NET Accelerator transforms this request into an ASP.NET request, receives the response, then transforms the response into a WSRP response. The .NET Accelerator is deployed as a stand-alone application on IIS. The WSRP Producer is deployed as a parent application on IIS and all ASP.NET modules that will be made available over WSRP are deployed as children of the WSRP Producer application. In this manner, the WSRP Producer acts more as a Request Filter than a proxy in the WSRP transactions between Producer and Consumer. Highly Recommended Enabling Logging Note: You can skip this section now, but you will most likely want to come back to it later, so why not just read it now? Logging is very helpful in tracking down the causes of any anomalies during testing of migrated portlets. To enable the WSRP Producer logging, update the Application_Start method in the Global.asax.cs for your .NET application by adding log4net.Config.XmlConfigurator.Configure(); IIS logs will usually (in a standard configuration) be in a sub folder under C:\WINDOWS\system32\LogFiles\W3SVC. WSRP Producer logs will be found at C:\Oracle\Middleware\WSRPProducerForDotNet\wsrpdefault\Logs\WSRPProducer.log InputTrace.webinfo and OutputTrace.webinfo are located under C:\Oracle\Middleware\WSRPProducerForDotNet\wsrpdefault and can be useful in debugging issues related to markup transformations. Things You Must Do Merge Web.Config Note: If you have been skipping all the sections that you can, now is the time to stop and pay attention J Because the existing .NET application will become a sub-application to the WSRP Producer, you will want to merge required settings from the existing Web.Config to the one in the WSRP Producer. Use the WSRP Producer Master Page The Master Page installed for the WSRP Producer provides common, hiddenform fields and JavaScripts to facilitate portlet instance management and display configuration when the child page is being rendered over WSRP. You add the Master Page by including it in the <@ Page declaration with MasterPageFile="~/portlets/Resources/MasterPages/WSRP.Master" . You then replace: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" > <HTML> <HEAD> With <asp:Content ID="ContentHead1" ContentPlaceHolderID="wsrphead" Runat="Server"> And </HEAD> <body> <form id="theForm" method="post" runat="server"> With </asp:Content> <asp:Content ID="ContentBody1" ContentPlaceHolderID="Main" Runat="Server"> And finally </form> </body> </HTML> With </asp:Content> In the event you already use Master Pages, adapt your existing Master Pages to be sub masters. See Nested ASP.NET Master Pages for a detailed reference of how to do this. It Happened to Me, It Might Happen to You…Or Not Watch for Use of Session or Request in OnInit In the event the .NET application being modified has pages developed to assume the user has been authenticated in an earlier page request there may be direct or indirect references in the OnInit method to request or session objects that may not have been created yet. This will vary from application to application, so the recommended approach is to test first. If there is an issue with a page running as a WSRP portlet then check for potential references in the OnInit method (including references by methods called within OnInit) to session or request objects. If there are, the simplest solution is to create a new method and then call that method once the necessary object(s) is fully available. I find doing this at the start of the Page_Load method to be the simplest solution. Case Sensitivity .NET languages are not case sensitive, but Java is. This means it is possible to have many variations of SRC= and src= or .JPG and .jpg. The preferred solution is to make these mark up instances all lower case in your .NET application. This will allow the default Rewriter rules in wsrp-producer.xml to work as is. If this is not practical, then make duplicates of any rules where an issue is occurring due to upper or mixed case usage in the .NET application markup and match the case in use with the duplicate rule. For example: <RewriterRule> <LookFor>(href=\"([^\"]+)</LookFor> <ChangeToAbsolute>true</ChangeToAbsolute> <ApplyTo>.axd,.css</ApplyTo> <MakeResource>true</MakeResource> </RewriterRule> May need to be duplicated as: <RewriterRule> <LookFor>(HREF=\"([^\"]+)</LookFor> <ChangeToAbsolute>true</ChangeToAbsolute> <ApplyTo>.axd,.css</ApplyTo> <MakeResource>true</MakeResource> </RewriterRule> While it is possible to write a regular expression that will handle mixed case usage, it would be long and strenous to test and maintain, so the recommendation is to use duplicate rules. Is it Still Relative? Some .NET applications base relative paths with a fixed root location. With the introduction of the WSRP Producer, the root has moved up one level. References to ~/ will need to be updated to ~/portlets and many ../ paths will need another ../ in front. I Can See You But I Can’t Find You This issue was first discovered while debugging modules with code that referenced the form on a page from the code-behind by name and/or id. The initial error presented itself as run-time error that was difficult to interpret over WSRP but seemed clear when run as straight ASP.NET as it indicated that the object with the form name did not exist. Since the form name was no longer valid after implementing the WSRP Master Page, the likely fix seemed to simply update the references in the code. However, as the WSRP Master Page is external to the code, a compile time error resulted: Error      155         The name 'form1' does not exist in the current context                C:\Oracle\Middleware\WSRPProducerForDotNet\wsrpdefault\portlets\legacywebsite\module\Screens \Reporting.aspx.cs                51           52           legacywebsite.module Much hair-pulling research later it was discovered that it was the use of the FindControl method causing the issue. FindControl doesn’t work quite as expected once a Master Page has been introduced as the controls become embedded in controls, require a recursion to find them that is not part of the FindControl method. In code where the page form is referenced by name, there are two steps to the solution. First, the form needs to be referenced in code generically with Page.Form. For example, this: ToggleControl ctrl = new ToggleControl(frmManualEntry, FunctionLibrary.ParseArrayLst(userObj.Roles)); Becomes this: ToggleControl ctrl = new ToggleControl(Page.Form, FunctionLibrary.ParseArrayLst(userObj.Roles)); Generally the form id is referenced in most ASP.NET applications as a path to a control on the form. To reach the control once a MasterPage has been added requires an additional method to recurse through the controls collections within the form and find the control ID. The following method (found at Rick Strahl's Web Log) corrects this very nicely: public static Control FindControlRecursive(Control Root, string Id) { if (Root.ID == Id) return Root; foreach (Control Ctl in Root.Controls) { Control FoundCtl = FindControlRecursive(Ctl, Id); if (FoundCtl != null) return FoundCtl; } return null; } Where the form name is not referenced, simply using the FindControlRecursive method in place of FindControl will be all that is necessary. Following the second part of the example referenced earlier, the method called with Page.Form changes its value extraction code block from this: Label lblErrMsg = (Label)frmRef.FindControl("lblBRMsg" To this: Label lblErrMsg = (Label) FunctionLibrary.FindControlRecursive(frmRef, "lblBRMsg" The Master That Won’t Step Aside In most migrations it is preferable to make as few changes as possible. In one case I ran across an existing Master Page that would not function as a sub-Master Page. While it would probably have been educational to trace down why, the expedient process of updating it to take the place of the WSRP Master Page is the route I took. The changes are highlighted below: … <asp:ContentPlaceHolder ID="wsrphead" runat="server"></asp:ContentPlaceHolder> </head> <body leftMargin="0" topMargin="0"> <form id="TheForm" runat="server"> <input type="hidden" name="key" id="key" value="" /> <input type="hidden" name="formactionurl" id="formactionurl" value="" /> <input type="hidden" name="handle" id="handle" value="" /> <asp:ScriptManager ID="ScriptManager1" runat="server" EnablePartialRendering="true" > </asp:ScriptManager> This approach did not work for all existing Master Pages, but fortunately all of the other existing Master Pages I have run across worked fine as a sub-Master to the WSRP Master Page. Moving On In Enterprise Portals, even after you get everything working, the work is not finished. Next you need to get it where everyone will work with it. Migration Planning Providing that the server where IIS is running is adequately sized, it is possible to run both the .NET Accelerator and the WSRP Producer on the same server during the upgrade process. The upgrade can be performed incrementally, i.e., one portlet at a time, if server administration processes support it. Those processes would include the ability to manage a second producer in the consuming portal and to change over individual portlet instances from one provider to the other. If processes or requirements demand that all portlets be cut over at the same time, it needs to be determined if this cut over should include a new producer, updating all of the portlets in the consumer, or if the WSRP Producer portlet configuration must maintain the naming conventions used by the .NET Accelerator and simply change the WSRP end point configured in the consumer. In some enterprises it may even be necessary to maintain the same WSDL end point, at which point the IIS configuration will be where the updates occur. The downside to such a requirement is that it makes rolling back very difficult, should the need arise. Location, Location, Location Not everyone wants the web application to have the descriptively obvious wsrpdefault location, or needs to create a second WSRP site on the same server. The instructions below are from the product team and, while targeted towards making a second site, will work for creating a site with a different name and then remove the old site. You can also change just the name in IIS. Manually Creating a WSRP Producer Site Instructions (NOTE: all executables used are the same ones used by the installer and “wsrpdev” will be the name of the new instance): 1. Copy C:\Oracle\Middleware\WSRPProducerForDotNet\wsrpdefault to C:\Oracle\Middleware\WSRPProducerForDotNet\wsrpdev. 2. Bring up a command window as an administrator 3. Run C:\Oracle\Middleware\WSRPProducerForDotNet\uninstall_resources\IISAppAccelSiteCreator.exe install WSRPProducers wsrpdev "C:\Oracle\Middleware\WSRPProducerForDotNet\wsrpdev" 8678 2.0.50727 4. Run C:\Oracle\Middleware\WSRPProducerForDotNet\uninstall_resources\PermManage.exe add FileSystem C:\Oracle\Middleware\WSRPProducerForDotNet\wsrpdev "NETWORK SERVICE" 3 1 5. Run C:\Oracle\Middleware\WSRPProducerForDotNet\uninstall_resources\PermManage.exe add FileSystem C:\Oracle\Middleware\WSRPProducerForDotNet\wsrpdev EVERYONE 1 1 6. Open up C:\Oracle\Middleware\WSRPProducerForDotNet\wsdl\1.0\WSRPService.wsdl and replace wsrpdefault with wsrpdev 7. Open up C:\Oracle\Middleware\WSRPProducerForDotNet\wsdl\2.0\WSRPService.wsdl and replace wsrpdefault with wsrpdev Tests: 1. Bring up a browser on the host itself and go to http://localhost:8678/wsrpdev/wsdl/1.0/WSRPService.wsdl and make sure that the URLs in the XML returned include the wsrpdev changes you made in step 6. 2. Bring up a browser on the host itself and see if the default sample comes up: http://localhost:8678/wsrpdev/portlets/ASPNET_AJAX_sample/default.aspx 3. Register the producer in WLP and test the portlet. Changing the Port used by WSRP Producer The pre-configured port for the WSRP Producer is 8678. You can change this port by updating both the IIS configuration and C:\Oracle\Middleware\WSRPProducerForDotNet\[WSRP_APP_NAME]\wsdl\1.0\WSRPService.wsdl. Do You Need to Migrate? Oracle Premier Support ended in November of 2010 for AquaLogic Interaction .NET Application Accelerator 1.x and Extended Support ends in November 2012 (see http://www.oracle.com/us/support/lifetime-support/lifetime-support-software-342730.html for other related dates). This means that integration with products released after November of 2010 is not supported. If having such support is the policy within your enterprise, you do indeed need to migrate. If changes in your enterprise cause your current solution with the .NET Accelerator to no longer function properly, you may need to migrate. Migration is a choice, and if the goals of your enterprise are to take full advantage of newer technologies then migration is certainly one activity you should be planning for.

  Read the article

• A WaspKiller Game with Silverlight 3, .NET RIA Services, MVP and MVVM Patterns Part 2

  In this second part, we will continue to discuss the WaspKiller game development—to extend the functionalities with the server-side database support. As mentioned in the first part, we’re going to rest upon another well-known design pattern, MVVM, to achieve the extension, and at the same time, introduce Microsoft .NET RIA Services framework to smooth out the whole architecture design.

  Read the article

• Unity3d Gravity script issues

  - by Joseph Le Brech

  I'm try this script out http://wiki.unity3d.com/index.php/Gravity and I'm having some issues with it (it seemed to work when I tried it with an old version of unity) the first issue is of collision, the objects (in my case spheres) will stick into each other rather than just touch. and the second is that when the objects collide one of the objects with continue it's trajectory. I'm thinking of rewriting the script from scratch unless someone can explain what's wrong with the script that i've got.

  Read the article

• SQLBits VI – The sixth sets

  - by Rob Farley

  My involvement stopped with the tagline, but SQLBits VI is on tomorrow. The theme of the event is Performance Tuning, which has nothing to do with Bruce Willis or dead people – unless Bruce Willis has just become a database expert and been shot for doing a dropping an index (some would say that’s a crime worthy of the death penalty). It’s a shame my involvement hasn’t been more, because it’s such a terrific event, and it would’ve been good to have been there for a second time. It’s a long way to...(read more)

  Read the article

• The embarrassingly obvious about SQL Server CE

  - by Edward Boyle

  I have been working with SQL servers in one form or another for almost two decades now. But I am new to SQL Server Compact Edition. In the past weeks I have been working with SQL Serve CE a lot. The SQL, not a problem, but the engine itself is very new to me. One of the issues I ran into was a simple SQL statement taking excusive amounts of time; by excessive, I mean over one second. I wrote a little code to time the method. Sometimes it took under one second, other times as long as three seconds. –But it was a simple update statement! As embarrassing as it is, why it was slow eluded me. I posted my issue to MSDN and I got a reply from ErikEJ (MS MVP) who runs the blog “Everything SQL Server Compact” . I know little to nothing about SQL Server Compact. This guy is completely obsessed very well versed in CE. If you spend any time in MSDN forums, it seems that this guy single handedly has the answer for every CE question that comes up. Anyway, he said: “Opening a connection to a SQL Server Compact database file is a costly operation, keep one connection open per thread (incl. your UI thread) in your app, the one on the UI thread should live for the duration of your app.” It hit me, all databases have some connection overhead and SQL Server CE is not a database engine running as a service drinking Jolt Cola waiting for someone to talk to him so he can spring into action and show off his quarter-mile sprint capabilities. Imagine if you had to start the SQL Server process every time you needed to make a database connection. Principally, that is what you are doing with SQL Server CE. For someone who has worked with Enterprise Level SQL Servers a lot, I had to come to the mental image that my Open connection to SQL Server CE is basically starting a service, my own private service, and by closing the connection, I am shutting down my little private service. After making the changes in my code, I lost any reservations I had with using CE. At present, my Data Access Layer class has a constructor; in that constructor I open my connection, I also have OpenConnection and CloseConnection methods, I also implemented IDisposable and clean up any connections in Dispose(). I am still finalizing how this assembly will function. – That’s beside the point. All I’m trying to say is: “Opening a connection to a SQL Server Compact database file is a costly operation”

  Read the article

• Sharing data between graphics and physics engine in the game?

  - by PolGraphic

  I'm writing the game engine that consists of few modules. Two of them are the graphics engine and the physics engine. I wonder if it's a good solution to share data between them? Two ways (sharing or not) looks like that: Without sharing data GraphicsModel{ //some common for graphics and physics data like position //some only graphic data //like textures and detailed model's verticles that physics doesn't need }; PhysicsModel{ //some common for graphics and physics data like position //some only physics data //usually my physics data contains A LOT more informations than graphics data } engine3D->createModel3D(...); physicsEngine->createModel3D(...); //connect graphics and physics data //e.g. update graphics model's position when physics model's position will change I see two main problems: A lot of redundant data (like two positions for both physics and graphics data) Problem with updating data (I have to manually update graphics data when physics data changes) With sharing data Model{ //some common for graphics and physics data like position }; GraphicModel : public Model{ //some only graphics data //like textures and detailed model's verticles that physics doesn't need }; PhysicsModel : public Model{ //some only physics data //usually my physics data contains A LOT more informations than graphics data } model = engine3D->createModel3D(...); physicsEngine->assingModel3D(&model); //will cast to //PhysicsModel for it's purposes?? //when physics changes anything (like position) in model //(which it treats like PhysicsModel), the position for graphics data //will change as well (because it's the same model) Problems here: physicsEngine cannot create new objects, just "assing" existing ones from engine3D (somehow it looks more anti-independent for me) Casting data in assingModel3D function physicsEngine and graphicsEngine must be careful - they cannot delete data when they don't need them (because second one may need it). But it's rare situation. Moreover, they can just delete the pointer, not the object. Or we can assume that graphicsEngine will delete objects, physicsEngine just pointers to them. Which way is better? Which will produce more problems in the future? I like the second solution more, but I wonder why most graphics and physics engines prefer the first one (maybe because they normally make only graphics or only physics engine and somebody else connect them in the game?). Have they any more hidden pros & contras?

  Read the article

• How to create Adhoc workflow in UCM

  - by vijaykumar.yenne

  UCM has an inbuilt workflow engine that can handle document centric workflow approval/rejection process to ensure the right set of assets go into the repository. Anybody who has gone through the documentation is aware that there are two types of work flows that can be defined using the Workflow Admin applet in UCM namely Criteria and Basic While criteria is an Automatic workflow  process based on certain metadata attributes (Security Group and One of the Metadata Fields) , basic workflow is a manual workflow that need to be initiated by the admin. Any workflow  that can be put on the white board can be translated into the UCM wokflow process and there are concepts like sub workflows, tokens, events. idoc scripting that be introduced to handle any kind of complex workflows. There is a specific Workflow Implementation guide that explains the concepts in detail. One of the standard queries i come across is how to handle adhoc workflows where at the time of contributing the content, the contributors would like to decide on the workflow to be initiated and the users to be picked for approval in each step, hence this post.This is what i want to acheive, i would like to display on my Checkin Screen on the kind of workflows that a contributor could choose from:Based on the Workflow the contributor chooses, the other metadata fields (Step One, Step Two and Step Three)  need to be filled in and these fields decide who the approvers are going to be.1. Create a criteria workflow called One_Step_Review2.create two tokens StepOne <$wfAddUser(xWorkflowStepOne, "user")$>,  OrginalAuthor  <$wfAddUser(wfGet("OriginalAuthor"), "user")$>View image3.create two steps in the work flow created (One_Step_Review)View image4. Edit Step1 of the Workflow and add the Step One token and select the review permissionView image5. In the exit conditions tab have atleast One reveiwerView image6. In the events tab add an entry event <$wfSet("OriginalAuthor",dDocAuthor)$> to capture the contributor who shall be notified in the second step of the workflowView image7. Add the second step Notify_Author to the workflow8. Add the original author token to the above step9.  Enable the workflow10. Open the configration manager applet and create a Metadata field Workflow with option list enabled and add the list of values as show hereView image11. Create another metadata field WorkflowStepOne with option list configured to the Users View. This shall display all the users registered with UCM, which when selected shall be associated with the tokens associated with the workflow. Refer the above token.View imageAs indicated in the above steps you could create multiple work flows and associate the custom metadata field values to the tokens so that the contributors can decide who can approve their  content.

  Read the article

• ASP.NET Frameworks and Raw Throughput Performance

  - by Rick Strahl

  A few days ago I had a curious thought: With all these different technologies that the ASP.NET stack has to offer, what's the most efficient technology overall to return data for a server request? When I started this it was mere curiosity rather than a real practical need or result. Different tools are used for different problems and so performance differences are to be expected. But still I was curious to see how the various technologies performed relative to each just for raw throughput of the request getting to the endpoint and back out to the client with as little processing in the actual endpoint logic as possible (aka Hello World!). I want to clarify that this is merely an informal test for my own curiosity and I'm sharing the results and process here because I thought it was interesting. It's been a long while since I've done any sort of perf testing on ASP.NET, mainly because I've not had extremely heavy load requirements and because overall ASP.NET performs very well even for fairly high loads so that often it's not that critical to test load performance. This post is not meant to make a point  or even come to a conclusion which tech is better, but just to act as a reference to help understand some of the differences in perf and give a starting point to play around with this yourself. I've included the code for this simple project, so you can play with it and maybe add a few additional tests for different things if you like. Source Code on GitHub I looked at this data for these technologies: ASP.NET Web API ASP.NET MVC WebForms ASP.NET WebPages ASMX AJAX Services  (couldn't get AJAX/JSON to run on IIS8 ) WCF Rest Raw ASP.NET HttpHandlers It's quite a mixed bag, of course and the technologies target different types of development. What started out as mere curiosity turned into a bit of a head scratcher as the results were sometimes surprising. What I describe here is more to satisfy my curiosity more than anything and I thought it interesting enough to discuss on the blog :-) First test: Raw Throughput The first thing I did is test raw throughput for the various technologies. This is the least practical test of course since you're unlikely to ever create the equivalent of a 'Hello World' request in a real life application. The idea here is to measure how much time a 'NOP' request takes to return data to the client. So for this request I create the simplest Hello World request that I could come up for each tech. Http Handler The first is the lowest level approach which is an HTTP handler. public class Handler : IHttpHandler { public void ProcessRequest(HttpContext context) { context.Response.ContentType = "text/plain"; context.Response.Write("Hello World. Time is: " + DateTime.Now.ToString()); } public bool IsReusable { get { return true; } } } WebForms Next I added a couple of ASPX pages - one using CodeBehind and one using only a markup page. The CodeBehind page simple does this in CodeBehind without any markup in the ASPX page: public partial class HelloWorld_CodeBehind : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { Response.Write("Hello World. Time is: " + DateTime.Now.ToString() ); Response.End(); } } while the Markup page only contains some static output via an expression:<%@ Page Language="C#" AutoEventWireup="false" CodeBehind="HelloWorld_Markup.aspx.cs" Inherits="AspNetFrameworksPerformance.HelloWorld_Markup" %> Hello World. Time is <%= DateTime.Now %> ASP.NET WebPages WebPages is the freestanding Razor implementation of ASP.NET. Here's the simple HelloWorld.cshtml page:Hello World @DateTime.Now WCF REST WCF REST was the token REST implementation for ASP.NET before WebAPI and the inbetween step from ASP.NET AJAX. I'd like to forget that this technology was ever considered for production use, but I'll include it here. Here's an OperationContract class: [ServiceContract(Namespace = "")] [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)] public class WcfService { [OperationContract] [WebGet] public Stream HelloWorld() { var data = Encoding.Unicode.GetBytes("Hello World" + DateTime.Now.ToString()); var ms = new MemoryStream(data); // Add your operation implementation here return ms; } } WCF REST can return arbitrary results by returning a Stream object and a content type. The code above turns the string result into a stream and returns that back to the client. ASP.NET AJAX (ASMX Services) I also wanted to test ASP.NET AJAX services because prior to WebAPI this is probably still the most widely used AJAX technology for the ASP.NET stack today. Unfortunately I was completely unable to get this running on my Windows 8 machine. Visual Studio 2012  removed adding of ASP.NET AJAX services, and when I tried to manually add the service and configure the script handler references it simply did not work - I always got a SOAP response for GET and POST operations. No matter what I tried I always ended up getting XML results even when explicitly adding the ScriptHandler. So, I didn't test this (but the code is there - you might be able to test this on a Windows 7 box). ASP.NET MVC Next up is probably the most popular ASP.NET technology at the moment: MVC. Here's the small controller: public class MvcPerformanceController : Controller { public ActionResult Index() { return View(); } public ActionResult HelloWorldCode() { return new ContentResult() { Content = "Hello World. Time is: " + DateTime.Now.ToString() }; } } ASP.NET WebAPI Next up is WebAPI which looks kind of similar to MVC. Except here I have to use a StringContent result to return the response: public class WebApiPerformanceController : ApiController { [HttpGet] public HttpResponseMessage HelloWorldCode() { return new HttpResponseMessage() { Content = new StringContent("Hello World. Time is: " + DateTime.Now.ToString(), Encoding.UTF8, "text/plain") }; } } Testing Take a minute to think about each of the technologies… and take a guess which you think is most efficient in raw throughput. The fastest should be pretty obvious, but the others - maybe not so much. The testing I did is pretty informal since it was mainly to satisfy my curiosity - here's how I did this: I used Apache Bench (ab.exe) from a full Apache HTTP installation to run and log the test results of hitting the server. ab.exe is a small executable that lets you hit a URL repeatedly and provides counter information about the number of requests, requests per second etc. ab.exe and the batch file are located in the \LoadTests folder of the project. An ab.exe command line  looks like this: ab.exe -n100000 -c20 http://localhost/aspnetperf/api/HelloWorld which hits the specified URL 100,000 times with a load factor of 20 concurrent requests. This results in output like this:   It's a great way to get a quick and dirty performance summary. Run it a few times to make sure there's not a large amount of varience. You might also want to do an IISRESET to clear the Web Server. Just make sure you do a short test run to warm up the server first - otherwise your first run is likely to be skewed downwards. ab.exe also allows you to specify headers and provide POST data and many other things if you want to get a little more fancy. Here all tests are GET requests to keep it simple. I ran each test: 100,000 iterations Load factor of 20 concurrent connections IISReset before starting A short warm up run for API and MVC to make sure startup cost is mitigated Here is the batch file I used for the test: IISRESET REM make sure you add REM C:\Program Files (x86)\Apache Software Foundation\Apache2.2\bin REM to your path so ab.exe can be found REM Warm up ab.exe -n100 -c20 http://localhost/aspnetperf/MvcPerformance/HelloWorldJsonab.exe -n100 -c20 http://localhost/aspnetperf/api/HelloWorldJson ab.exe -n100 -c20 http://localhost/AspNetPerf/WcfService.svc/HelloWorld ab.exe -n100000 -c20 http://localhost/aspnetperf/handler.ashx > handler.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/HelloWorld_CodeBehind.aspx > AspxCodeBehind.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/HelloWorld_Markup.aspx > AspxMarkup.txt ab.exe -n100000 -c20 http://localhost/AspNetPerf/WcfService.svc/HelloWorld > Wcf.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/MvcPerformance/HelloWorldCode > Mvc.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/api/HelloWorld > WebApi.txt I ran each of these tests 3 times and took the average score for Requests/second, with the machine otherwise idle. I did see a bit of variance when running many tests but the values used here are the medians. Part of this has to do with the fact I ran the tests on my local machine - result would probably more consistent running the load test on a separate machine hitting across the network. I ran these tests locally on my laptop which is a Dell XPS with quad core Sandibridge I7-2720QM @ 2.20ghz and a fast SSD drive on Windows 8. CPU load during tests ran to about 70% max across all 4 cores (IOW, it wasn't overloading the machine). Ideally you can try running these tests on a separate machine hitting the local machine. If I remember correctly IIS 7 and 8 on client OSs don't throttle so the performance here should be Results Ok, let's cut straight to the chase. Below are the results from the tests… It's not surprising that the handler was fastest. But it was a bit surprising to me that the next fastest was WebForms and especially Web Forms with markup over a CodeBehind page. WebPages also fared fairly well. MVC and WebAPI are a little slower and the slowest by far is WCF REST (which again I find surprising). As mentioned at the start the raw throughput tests are not overly practical as they don't test scripting performance for the HTML generation engines or serialization performances of the data engines. All it really does is give you an idea of the raw throughput for the technology from time of request to reaching the endpoint and returning minimal text data back to the client which indicates full round trip performance. But it's still interesting to see that Web Forms performs better in throughput than either MVC, WebAPI or WebPages. It'd be interesting to try this with a few pages that actually have some parsing logic on it, but that's beyond the scope of this throughput test. But what's also amazing about this test is the sheer amount of traffic that a laptop computer is handling. Even the slowest tech managed 5700 requests a second, which is one hell of a lot of requests if you extrapolate that out over a 24 hour period. Remember these are not static pages, but dynamic requests that are being served. Another test - JSON Data Service Results The second test I used a JSON result from several of the technologies. I didn't bother running WebForms and WebPages through this test since that doesn't make a ton of sense to return data from the them (OTOH, returning text from the APIs didn't make a ton of sense either :-) In these tests I have a small Person class that gets serialized and then returned to the client. The Person class looks like this: public class Person { public Person() { Id = 10; Name = "Rick"; Entered = DateTime.Now; } public int Id { get; set; } public string Name { get; set; } public DateTime Entered { get; set; } } Here are the updated handler classes that use Person: Handler public class Handler : IHttpHandler { public void ProcessRequest(HttpContext context) { var action = context.Request.QueryString["action"]; if (action == "json") JsonRequest(context); else TextRequest(context); } public void TextRequest(HttpContext context) { context.Response.ContentType = "text/plain"; context.Response.Write("Hello World. Time is: " + DateTime.Now.ToString()); } public void JsonRequest(HttpContext context) { var json = JsonConvert.SerializeObject(new Person(), Formatting.None); context.Response.ContentType = "application/json"; context.Response.Write(json); } public bool IsReusable { get { return true; } } } This code adds a little logic to check for a action query string and route the request to an optional JSON result method. To generate JSON, I'm using the same JSON.NET serializer (JsonConvert.SerializeObject) used in Web API to create the JSON response. WCF REST   [ServiceContract(Namespace = "")] [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)] public class WcfService { [OperationContract] [WebGet] public Stream HelloWorld() { var data = Encoding.Unicode.GetBytes("Hello World " + DateTime.Now.ToString()); var ms = new MemoryStream(data); // Add your operation implementation here return ms; } [OperationContract] [WebGet(ResponseFormat=WebMessageFormat.Json,BodyStyle=WebMessageBodyStyle.WrappedRequest)] public Person HelloWorldJson() { // Add your operation implementation here return new Person(); } } For WCF REST all I have to do is add a method with the Person result type.   ASP.NET MVC public class MvcPerformanceController : Controller { // // GET: /MvcPerformance/ public ActionResult Index() { return View(); } public ActionResult HelloWorldCode() { return new ContentResult() { Content = "Hello World. Time is: " + DateTime.Now.ToString() }; } public JsonResult HelloWorldJson() { return Json(new Person(), JsonRequestBehavior.AllowGet); } } For MVC all I have to do for a JSON response is return a JSON result. ASP.NET internally uses JavaScriptSerializer. ASP.NET WebAPI public class WebApiPerformanceController : ApiController { [HttpGet] public HttpResponseMessage HelloWorldCode() { return new HttpResponseMessage() { Content = new StringContent("Hello World. Time is: " + DateTime.Now.ToString(), Encoding.UTF8, "text/plain") }; } [HttpGet] public Person HelloWorldJson() { return new Person(); } [HttpGet] public HttpResponseMessage HelloWorldJson2() { var response = new HttpResponseMessage(HttpStatusCode.OK); response.Content = new ObjectContent<Person>(new Person(), GlobalConfiguration.Configuration.Formatters.JsonFormatter); return response; } } Testing and Results To run these data requests I used the following ab.exe commands:REM JSON RESPONSES ab.exe -n100000 -c20 http://localhost/aspnetperf/Handler.ashx?action=json > HandlerJson.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/MvcPerformance/HelloWorldJson > MvcJson.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/api/HelloWorldJson > WebApiJson.txt ab.exe -n100000 -c20 http://localhost/AspNetPerf/WcfService.svc/HelloWorldJson > WcfJson.txt The results from this test run are a bit interesting in that the WebAPI test improved performance significantly over returning plain string content. Here are the results:   The performance for each technology drops a little bit except for WebAPI which is up quite a bit! From this test it appears that WebAPI is actually significantly better performing returning a JSON response, rather than a plain string response. Snag with Apache Benchmark and 'Length Failures' I ran into a little snag with Apache Benchmark, which was reporting failures for my Web API requests when serializing. As the graph shows performance improved significantly from with JSON results from 5580 to 6530 or so which is a 15% improvement (while all others slowed down by 3-8%). However, I was skeptical at first because the WebAPI test reports showed a bunch of errors on about 10% of the requests. Check out this report: Notice the Failed Request count. What the hey? Is WebAPI failing on roughly 10% of requests when sending JSON? Turns out: No it's not! But it took some sleuthing to figure out why it reports these failures. At first I thought that Web API was failing, and so to make sure I re-ran the test with Fiddler attached and runiisning the ab.exe test by using the -X switch: ab.exe -n100 -c10 -X localhost:8888 http://localhost/aspnetperf/api/HelloWorldJson which showed that indeed all requests where returning proper HTTP 200 results with full content. However ab.exe was reporting the errors. After some closer inspection it turned out that the dates varying in size altered the response length in dynamic output. For example: these two results: {"Id":10,"Name":"Rick","Entered":"2012-09-04T10:57:24.841926-10:00"} {"Id":10,"Name":"Rick","Entered":"2012-09-04T10:57:24.8519262-10:00"} are different in length for the number which results in 68 and 69 bytes respectively. The same URL produces different result lengths which is what ab.exe reports. I didn't notice at first bit the same is happening when running the ASHX handler with JSON.NET result since it uses the same serializer that varies the milliseconds. Moral: You can typically ignore Length failures in Apache Benchmark and when in doubt check the actual output with Fiddler. Note that the other failure values are accurate though. Another interesting Side Note: Perf drops over Time As I was running these tests repeatedly I was finding that performance steadily dropped from a startup peak to a 10-15% lower stable level. IOW, with Web API I'd start out with around 6500 req/sec and in subsequent runs it keeps dropping until it would stabalize somewhere around 5900 req/sec occasionally jumping lower. For these tests this is why I did the IIS RESET and warm up for individual tests. This is a little puzzling. Looking at Process Monitor while the test are running memory very quickly levels out as do handles and threads, on the first test run. Subsequent runs everything stays stable, but the performance starts going downwards. This applies to all the technologies - Handlers, Web Forms, MVC, Web API - curious to see if others test this and see similar results. Doing an IISRESET then resets everything and performance starts off at peak again… Summary As I stated at the outset, these were informal to satiate my curiosity not to prove that any technology is better or even faster than another. While there clearly are differences in performance the differences (other than WCF REST which was by far the slowest and the raw handler which was by far the highest) are relatively minor, so there is no need to feel that any one technology is a runaway standout in raw performance. Choosing a technology is about more than pure performance but also about the adequateness for the job and the easy of implementation. The strengths of each technology will make for any minor performance difference we see in these tests. However, to me it's important to get an occasional reality check and compare where new technologies are heading. Often times old stuff that's been optimized and designed for a time of less horse power can utterly blow the doors off newer tech and simple checks like this let you compare. Luckily we're seeing that much of the new stuff performs well even in V1.0 which is great. To me it was very interesting to see Web API perform relatively badly with plain string content, which originally led me to think that Web API might not be properly optimized just yet. For those that caught my Tweets late last week regarding WebAPI's slow responses was with String content which is in fact considerably slower. Luckily where it counts with serialized JSON and XML WebAPI actually performs better. But I do wonder what would make generic string content slower than serialized code? This stresses another point: Don't take a single test as the final gospel and don't extrapolate out from a single set of tests. Certainly Twitter can make you feel like a fool when you post something immediate that hasn't been fleshed out a little more <blush>. Egg on my face. As a result I ended up screwing around with this for a few hours today to compare different scenarios. Well worth the time… I hope you found this useful, if not for the results, maybe for the process of quickly testing a few requests for performance and charting out a comparison. Now onwards with more serious stuff… Resources Source Code on GitHub Apache HTTP Server Project (ab.exe is part of the binary distribution)© Rick Strahl, West Wind Technologies, 2005-2012Posted in ASP.NET  Web Api   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

  Read the article

• Tom Cruise: Meet Fusion Apps UX and Feel the Speed

  - by ultan o'broin

  Unfortunately, I am old enough to remember, and now to admit that I really loved, the movie Top Gun. You know the one - Tom Cruise, US Navy F-14 ace pilot, Mr Maverick, crisis of confidence, meets woman, etc., etc. Anyway, one of more memorable lines (there were a few) was: "I feel the need, the need for speed." I was reminded of Tom Cruise recently. Paraphrasing a certain Senior Vice President talking about Oracle Fusion Applications and user experience at an all-hands meeting, I heard that: Applications can never be too easy to use. Performance can never be too fast. Developers, assume that your code is always "on". Perfect. You cannot overstate the user experience importance of application speed to users, or at least their perception of speed. We all want that super speed of execution and performance, and increasingly so as enterprise users bring the expectations of consumer IT into the work environment. Sten Vesterli (@stenvesterli), an Oracle Fusion Applications User Experience Advocate, also addressed the speed point artfully at an Oracle Usability Advisory Board meeting in Geneva. Sten asked us that when we next Googled something, to think about the message we see that Google has found hundreds of thousands or millions of results for us in a split second (for example, About 8,340,000 results (0.23 seconds)). Now, how many results can we see and how many can we use immediately? Yet, this simple message communicating the total results available to us works a special magic about speed, delight, and excitement that Google has made its own in the search space. And, guess what? The Oracle Application Development Framework table component relies on a similar "virtual performance boost", says Sten, when it displays the first 50 records in a table, and uses a scrollbar indicating the total size of the data record set. The user scrolls and the application automatically retrieves more records as needed. Application speed and its perception by users is worth bearing in mind the next time you're at a customer site and the IT Department demands that you retrieve every record from the database. Just think of... Dave Ensor: I'll give you all the rows you ask for in one second. If you promise to use them. (Again, hat tip to Sten.) And then maybe think of... Tom Cruise. And if you want to read about the speed of Oracle Fusion Applications, and what that really means in terms of user productivity for your entire business, then check out the Oracle Applications User Experience Oracle Fusion Applications white papers on the usable apps website.

  Read the article

• Bad Screen Flicker from video recording of recordmydesktop

  - by Tarun

  I have ubuntu 11.10 and I installed recordmydesktop. Video recording from recordmydesktop always result in screen flicker. In recording I see half of the screen moving forward while half would be stuck. I checked the settings and "Frame per Second" is set to 15 One such recording is available here - http://www.youtube.com/watch?v=QafF44m2Ttk&feature=youtu.be I am quite new to Ubuntu and not sure what is wrong.

  Read the article

• Working with Temporal Data in SQL Server

  - by Dejan Sarka

  My third Pluralsight course, Working with Temporal Data in SQL Server, is published. I am really proud on the second part of the course, where I discuss optimization of temporal queries. This was a nearly impossible task for decades. First solutions appeared only lately. I present all together six solutions (and one more that is not a solution), and I invented four of them. http://pluralsight.com/training/Courses/TableOfContents/working-with-temporal-data-sql-server

  Read the article

• Guru Of the Week n° 44 : copie sur écriture - deuxième partie, un article de Herb Sutter traduit par la rédaction C++

  Second article consacré à l'idiome "copie sur écriture" suite à la première partie. Dans cet article, Herb Sutter développe l'exemple d'une classe de chaîne de caractères utilisant cet idiome. Guru Of the Week n° 44 : copie sur écriture - deuxième partie Que pensez-vous de la différence entre std::string et la classe proposée dans cet article ? Retrouver l'ensemble des Guru of the Week sur la page d'index....

  Read the article

< Previous Page | 370 371 372 373 374 375 376 377 378 379 380 381  | Next Page >