IIS Application Pool Recycling

Applies To: Windows Server 2008

Internet Information Services (IIS) application pools can be periodically recycled to avoid unstable states that can lead to application crashes, hangs, or memory leaks. By default, application pool recycling is overlapped, which means that the worker process that is to be shut down is kept running until after a new worker process is started. After a new worker process starts, new requests are passed to it. The old worker process shuts down after it finishes processing its existing requests, or after a configured time-out, whichever comes first. This way of recycling ensures uninterrupted service to clients. However, if an application in the application pool cannot run more than one instance of itself at a time, overlapping rotation can be disabled.

Events

Event ID Source Message

2262

Microsoft-Windows-IIS-WMSVC

ISAPI '%1' reported itself as unhealthy for the following reason: '%2'.

2263

Microsoft-Windows-IIS-WMSVC

ISAPI '%1' reported itself as unhealthy. No reason was given by the ISAPI.

5070

Microsoft-Windows-WAS

The Windows Process Activation Service failed to issue recycle requests to all worker processes of application pool '%1'. The data field contains the error number.

5074

Microsoft-Windows-WAS

A worker process with process id of '%1' serving application pool '%2' has requested a recycle because the worker process reached its allowed processing time limit.

5075

Microsoft-Windows-WAS

A worker process with process id of '%1' serving application pool '%2' has requested a recycle because it reached its allowed request limit.

5076

Microsoft-Windows-WAS

A worker process with process id of '%1' serving application pool '%2' has requested a recycle because it reached its scheduled recycle time.

5077

Microsoft-Windows-WAS

A worker process with process id of '%1' serving application pool '%2' has requested a recycle because it reached its virtual memory limit.

5078

Microsoft-Windows-WAS

An ISAPI reported an unhealthy condition to its worker process. Therefore, the worker process with process id of '%1' serving application pool '%2' has requested a recycle.

5079

Microsoft-Windows-WAS

An administrator has requested a recycle of all worker processes in application pool '%1'.

5080

Microsoft-Windows-WAS

The worker processes serving application pool '%1' are being recycled due to 1 or more configuration changes in the application pool properties which necessitate a restart of the processes.

5081

Microsoft-Windows-WAS

The worker processes serving application pool '%1' are being recycled due to detected problems with the IIS configuration store that may make current cached metadata invalid.

5093

Microsoft-Windows-WAS

The Windows Process Activation Service failed to overlap recycle for application pool '%1' worker process '%2'. The data field contains the error number.

5117

Microsoft-Windows-WAS

A worker process with process id of '%1' serving application pool '%2' has requested a recycle because it reached its private bytes memory limit.

5186

Microsoft-Windows-WAS

A worker process with process id of '%1' serving application pool '%2' was shutdown due to inactivity. Application Pool timeout configuration was set to %3 minutes. A new worker process will be started when needed.

IIS Application Pool

Internet Information Services (IIS) 7.0