Problems with IIS, isapi_redirect.dll and Tomcat under high load
Posted on 2007-11-28
I have a Java application running on Tomcat 5.5 on a Win2k box. The box runs IIS 5 connected to Tomcat using JK 1.2. During periods of our highest load (around 50 page requests per minute) we have a failure. User's get a browser error (I think it's page unavailable) looking like the application has gone down.
In the IIS logs I can see requests still coming in as expected, and IIS still serves up images ok. Also if I log into the server and connect to Tomcat directly on port 8080 I can load the application (albeit without images) and confirm it is still running correctly.
The only way to rectify the fault is to restart Tomcat, even though this seems to still be running ok
I have turned on logging to debug for the JK connector but can't see anything useful in the logs. I have also tried upgrading JK to the latest version of the DLL (7th aug '07).
If anyone has any recommendations for what I can try I'd be very grateful. Thanks