IIS 7 and Above
Unexplained Application end's or unloads
Last post Aug 21, 2017 09:19 AM by Yuk Ding
Aug 01, 2017 09:42 PMfirstname.lastname@example.org|LINK
Since June 19 we are experiencing unexplained and undesired
recycles of application pool worker processes ends or unloads of Applications or Application Domains.
The Application Pool has a scheduled 3am recycle. Bit since June 19th we are experiencing additional unexplained daily
recycles Application End's between 5am and 5:30am. We are not yet able to find the cause or trigger. Not in the IIS Admin settings nor in the Event Logs nor in the Task Scheduler.
We luckily do have a call stack of the
recycle, sent by email of IIS Admin:
Current StackTrace (max 30 frames deep):
Where should we further search for the cause, the trigger of this
Aug 02, 2017 08:02 AM|Yuk Ding|LINK
So could you provide the recycle configuration in application pool advanced setting? If there it is not an abnormal recycle, there should have a log entry in event viewer system log . Frist of all, just ensure you didn't set the recycle for specific time
in IIS manager->application pool level->recycling->ensure the specific time checkbox is unchecked.
If there is no log entry for recycling, I assume you do have an idle time out configuration for IIS manager, then when application pool become inactivity between 5am and 5:30am, the application pool get recycled. You may need to check the IIS log, dump file,
performance monitor for more information.
In addition, just ensure all the options under generate event recycle log entry has been selected to true in application pool advanced setting.
Aug 05, 2017 05:47 PM|Paul Lynch|LINK
By default all application recycle events are not logged to the event log. In order to capture all of them you need to run this command from an elevated Powershell session :
Set-WebConfigurationProperty '/system.applicationHost/applicationPools/applicationPoolDefaults' -Name recycling.logEventOnRecycle -value "Time, Requests, Schedule, Memory, IsapiUnhealthy, OnDemand, ConfigChange, PrivateMemory"
The event log entries that these recycle events can generate are documented here :
Aug 11, 2017 04:17 PMemail@example.com|LINK
Sorry for not replying. I got into a muddle with accounts and saw that I didn't even have a good email address set for this account (...@outlook.com??). And that my proper email address was showing publicly as my avatar/user
name :-( Which I now changed in my profile but it's still showing for this post, which I hope is just microsoft servers caching synch thing...
Thanks Paul and Yuk for the feedback.
I have done further research (but not yet Paul's tip), and found that it is NOT an AppPool Recycle. Because the w3wp.exe process is always still the 3am process, after our normal scheduled 3am nightly recycles. So this means it is application ends or applicationcontext
unloads or something like that.
We are now coding in for a next version which should then give us the reason, in the email that our Application End event handler sends.
I'll let you know here when we discover the cause...
Aug 21, 2017 09:19 AM|Yuk Ding|LINK
Maybe you need to analyze the dump file to figure out what's going on with this issue.