I've a web application running on windows server 2008 x64. Application use cache to save some data but while working this data disappeared. it seams that the application pool recycles.
I disabled the application pool recycling (no over lapping recycle, privet memory limit is zero also the virtual memory is zero and no interval limits specified ).
after these configurations application pool recycles!
is there any default windows configuration that limits the application pools worker process?
Related
We have Windows 2003 Server IIS 6.0 and Windows 2008 Server IIS 7.0
Issue : In IIS 6.0, when Default App pool crashes it shut down other App pools as well.
Whether the Default App pool crashes and shut down will affect other App pools running in the same farm / IIS ?
Other Pools
One pool can affect other in this cases.
Lock some global resource that the rest need to access and all pools gets time outs.
Eat the servers power with bad loops.
Each pool have their space that work aside from the other, so general speaking you need to look for what they have common, like if you use session database and the one locks it for long time, and the other is gets time outs many time together with the first one and fell also on Rapid-fail protection.
Pool it self
The pool is connected with many apps, so when this pool crash, is affect and all apps/web sites that are connected with this.
When this is a problem.
When the pool crash many times and is felt on the "Rapid-Fail Protection" that make the pool to permanently shut down.
When some site is keep the pool inside a loop that eats all resource of it and the power of your server.
here is an example : How do I crash the App Pool?
For the first case you must go to your pool and turn off the "Rapid-Fail Protection". For the second case you need to locate the problem and isolate.
More to read:
Rapid Fail Protection
Configuring Rapid-Fail Protection
IIS app pools, worker processes, app domains
Have a web application running on several servers. Two of the servers are having issues where the application pool becomes disabled. Message in the Event viewer System Log: Application pool 'xxxxx' is being automatically disabled due to a series of failures in the process(es) serving that application pool.
Just prior to this message are several other 'Warning' Messages: A process serving application pool 'xxxxx' suffered a fatal communication error with the Windows Process Activation Service. The process id was '1072'. The data field contains the error number. Or A process serving application pool 'xxxxx' terminated unexpectedly. The process id was '3644'. The process exit code was '0x0'.
Running IIS 7. The servers that are failing are running 2008R2 with Service Pack1 and the other are running 2008R2 (no Service Pack).
In the HTTP log right before I see the AppOffline message, there are the several Connection_Abandoned_By_ReqQueue and Client_Reset messages.
I have read and reread many posting about changing the Rapid-Fail Protection settings from the default of failure interval (minutes) 5 and Maximum failures 5 as I can see that after five failures in five minutes the AppPool is stopped. However, doing this just changes the number of issues during a particular time before the AppPool will be stopped and not really addressing the root cause of the problem.
What is the correct method for determine why the application is failing?
Could the difference in service pack on the server be a culprit?
Thanks.
We have a ASP.NET/WCF app hosted in Window Server 2012 (IIS 7). We used the basicHttpBinding. This ASP.NET/WCF application exposes two methods; one is to receive messages and the other is to download a text file (1MB) onto the server.
On another server, we have ASP.NET hosted in Window Server 2012 (IIS 7) which is the client that consumes the exposed method mentioned earlier. This client application sends a message and uploads a text file at a high frequency. This communication between this ASP.NET/WCF application and client application works fine for a few hours until we get the following error at the ASP.NET/WCF side.
Application pool 'XXXXXXXXXX' is being automatically disabled due to a series of failures in the process(es) serving that application pool.
So, could you please shine some light regarding this issue that we are facing?
This is due to something called "Rapid Fail Protection." When your underlying application crashes a certain number of times in a certain time period, the application pool is automatically disabled.
The default settings are 5 crashes in 5 minutes, but you can configure this yourself. See this link for details.
I am in a bit of confusion here. In IIS 5.0 all the ASP.NET applications run inside the same worker process(aspnet_wp.exe). The various applications are isolated by appdomain. I believe the fundamental functionality of an appdomain is to provide application isolation within a process. Now on to IIS 6.0. I have read about application pools in IIS 6. A lot of sites say that in IIS 5.0 when there is a problem with an application it affects the other applications. But isnt that safeguarded by appdomains? I am being told that application pools in IIS 6.0 prevent that mishaps. I am a bit confused here as to what exactly is advantage that application pools provide over IIS 5.0. I have also been told that in IIS 6 worker process isolation mode, configuring different application pools(and thereby different worker processes) is a perfomant thing to do. But spawning new processes increases the memory utilization and how can it be claimed to be a performant way to do things? Also how does the HTTP.SYS know to route the request to the concerned application poool?
Don't get application pools and AppDomains confused. An AppDomain is a isolation boundary within a process. They are designed to isolate and provide security around managed code that is executing.
Application pools are a feature of IIS that allow a pool to handle requests for multiple sites. They handle this by running multiple AppDomain instances in the worker processes (aspnet_wp.exe, or w3wp.exe). Although technically you can run multiple AppDomain instances per site, generally it is a single AppDomain per IIS Application.
If you have multiple sites in a single application pool (and this sharing the worker processes), if one of those sites starts consuming a lot of resources, this can directly effect the other sites running in the same application pool.
By grouping (and segregating) sites in logical groups (application pools), you can better manage how sites behave.
HTTP.SYS is a kernel mode driver stack that is part of the Windows subsystems. It provides management of the HTTP protocol in kernel mode (versions prior to IIS6 used winsock in user mode). With HTTP.SYS running at the kernel level, should a worker process fail, the request can be queued, and then forwarded to a new worker process which will be spun up.
When you create a site in IIS6, it registers the site with HTTP.SYS which can then route requests coming in to the appropriate worker process.
The Appdomain is about sharing data
http://msdn.microsoft.com/en-us/library/system.appdomain.aspx
and in IIS 6 you can append several applications to an application pool. If you have 2 applications in the same application pool and one of them keeps crashing, it affects the other and IIS will decide to shutdown the whole application pool because of the instability.
Therefore, if you have critical applications, it is recommended to keep them in their own application pool. If you have multiple apps in IIS, you route the requests with the hostheaders (or extra external IIP addresses)
extra resource that recommends an application pool for each production website: http://forums.iis.net/t/1151476.aspx
a nice resource which explains the difference between 5.0 and 6.0 with isolation:
http://www.tech-faq.com/understanding-iis-5-and-iis-6.html
Which event log files does the IIS 7.0 Application Pool Recycling log to?
I want to check out at what time the default app pool automatically recylces.
They are logged in the Windows Event Viewer. On Win7 they are in Windows Logs > System - filter for Source = WAS
A typical message may read:
A worker process with process id of '5916' serving application pool 'DefaultAppPool' was shutdown due to inactivity. Application Pool timeout configuration was set to 20 minutes. A new worker process will be started when needed.