Databases
StackOverflow2013
Postsdbo
POShould Application_End fire on an automatic App Pool Recycle?
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POShould Application_End fire on an automatic App Pool Recycle?
    primarykey
    data
    text
    <p>I have read <a href="https://stackoverflow.com/questions/5320180/asp-net-mvc-why-does-my-app-keep-restarting">this</a>, <a href="https://stackoverflow.com/questions/844050/rule-of-thumb-for-amount-of-usage-memory-it-takes-to-make-a-worker-process-recyc">this</a>, <a href="https://stackoverflow.com/questions/10830633/determine-memory-used-by-asp-net-cache-in-shared-hosting">this</a> and <a href="http://blogs.msdn.com/tess/archive/2006/09/06/net-memory-usage-a-restaurant-analogy.aspx" rel="nofollow noreferrer">this</a> plus a dozen other posts/blogs.</p> <p>I have an ASP.Net app in shared hosting that is frequently recycling. We use NLog and have the following code in global.asax </p> <pre><code>void Application_Start(object sender, EventArgs e) { NLog.Logger logger = NLog.LogManager.GetCurrentClassLogger(); logger.Debug("\r\n\r\nAPPLICATION STARTING\r\n\r\n"); } protected void Application_OnEnd(Object sender, EventArgs e) { NLog.Logger logger = NLog.LogManager.GetCurrentClassLogger(); logger.Debug("\r\n\r\nAPPLICATION_OnEnd\r\n\r\n"); } void Application_End(object sender, EventArgs e) { HttpRuntime runtime = (HttpRuntime)typeof(System.Web.HttpRuntime).InvokeMember("_theRuntime", BindingFlags.NonPublic | BindingFlags.Static | BindingFlags.GetField, null, null, null); if (runtime == null) return; string shutDownMessage = (string)runtime.GetType().InvokeMember("_shutDownMessage", BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.GetField, null, runtime, null); string shutDownStack = (string)runtime.GetType().InvokeMember("_shutDownStack", BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.GetField, null, runtime, null); ApplicationShutdownReason shutdownReason = System.Web.Hosting.HostingEnvironment.ShutdownReason; NLog.Logger logger = NLog.LogManager.GetCurrentClassLogger(); logger.Debug(String.Format("\r\n\r\nAPPLICATION END\r\n\r\n_shutDownReason = {2}\r\n\r\n _shutDownMessage = {0}\r\n\r\n_shutDownStack = {1}\r\n\r\n", shutDownMessage, shutDownStack, shutdownReason)); } void Application_Error(object sender, EventArgs e) { NLog.Logger logger = NLog.LogManager.GetCurrentClassLogger(); logger.Debug("\r\n\r\nApplication_Error\r\n\r\n"); } </code></pre> <p>Our log file is littered with "APPLICATION STARTING" entries, but neither <code>Application_OnEnd</code>, <code>Application_End</code>, nor <code>Application_Error</code> are ever fired during these spontaneous restarts. I know they are working because there are entries for touching the web.config or /bin files. We also ran a memory overload test and can trigger an <code>OutOfMemoryException</code> which is caught in <code>Application_Error</code>.</p> <p>We are trying to determine whether the virtual memory limit is causing the recycling. We have added <code>GC.GetTotalMemory(false)</code> throughout the code, but this is for <strong>all of .Net</strong>, not just our App´s pool, correct? We've also tried</p> <pre><code>var oPerfCounter = new PerformanceCounter(); oPerfCounter.CategoryName = "Process"; oPerfCounter.CounterName = "Virtual Bytes"; oPerfCounter.InstanceName = "iisExpress"; logger.Debug("Virtual Bytes: " + oPerfCounter.RawValue + " bytes"); </code></pre> <p>but don't have permission in shared hosting.</p> <p>I've monitored the app on a dev server with the same requests that caused the recycles in production with ANTS Memory Profiler attached and can't seem to find a culprit. We have also run it with a debugger attached in dev to check for uncaught exceptions in spawned threads that might cause the app to abort.</p> <p>My questions are these:</p> <ul> <li>How can I effectively monitor memory usage in shared hosting to tell how much my application is consuming prior to an application recycle?</li> <li>Why are the Application_[End/OnEnd/Error] handlers in global.asax not being called?</li> <li>How else can I determine what is causing these recycles?</li> </ul> <p>Thanks.</p> <p>EDIT: Based on answer by @Jani Hyytiäinen</p> <p>Scenario: Thread #1 begins and is followed by thread #2. Thread #1 hits memory limit but continues processing. Thread #3 begins. Thread #1 finishes, but #2 processes more than 60 seconds after #1 has hit the memory limit. </p> <p>The pool then ungracefully aborts? What http responses will #2 &amp; #3 receive (These are AJAX calls, but I am getting 504 errors in Fiddler)?<br> Is the request for #3 accepted or does it just queue until a new pool has started up?<br> Is there any way to know that the memory limit has been hit or is about to be?</p> <p>Any strategies welcome.</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USCommunity
    1. USLaramie
    plurals
    1. PL
      singulars
      1. LTLinked
    2. PL
      singulars
      1. LTLinked
    3. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POShould Application_End fire on an automatic App Pool Recycle?
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. POShould Application_End fire on an automatic App Pool Recycle?
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. POShould Application_End fire on an automatic App Pool Recycle?
      1. This table or related slice is empty.
      1. VTUpMod
    1. COThe HTTP 504 Gateway Timeout not actually returned by your site since the error itself means the resource requested by url did not respond in a timely manner. In your case, probably because the app pool was shut down and new one hadn't yet started up. When application pool shuts down, all the threads in it will abort with it. Which most definitely leads to HTTP 504 on threads #2 and #3
      singulars
      1. POShould Application_End fire on an automatic App Pool Recycle?
      1. USJani Hyytiäinen
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload