Bug 63993

Summary: Fatal error EXCEPTION_ACCESS_VIOLATION are thrown while the load test scenario includes multiple concurrent connections
Product: Tomcat 7 Reporter: Michael Mishalov <michael.mishalov>
Component: CatalinaAssignee: Tomcat Developers Mailing List <dev>
Status: RESOLVED WONTFIX    
Severity: normal    
Priority: P2    
Version: 7.0.94   
Target Milestone: ---   
Hardware: PC   
OS: All   
Attachments: generated thread dump while due EXCEPTION_ACCESS_VIOLATION error

Description Michael Mishalov 2019-12-08 22:44:22 UTC 
Created attachment 36911 [details]
generated thread dump while due EXCEPTION_ACCESS_VIOLATION error

Fatal error EXCEPTION_ACCESS_VIOLATION are thrown while the load test scenario include 1K concurrent connections 

While running performance test of our application we see random spikes of CPU utilisation and increases on Open AM active sessions without any increase in load. 
After certain time Tomcat crashes with EXCEPTION_ACCESS_VIOLATION exception.

We tested the same scenario with different connectors (APR (native) and BIO) on Windows Server 2012R2 and on Windows Server 2016 and also filtered out all application specific scenarios to isolate the root course of the issue. 

During our investigation we also found two issues reported previously that may be closely related to this one as well, however it seems that version we are using already have native library that contains this fix.

https://bz.apache.org/bugzilla/show_bug.cgi?id=56313
https://bz.apache.org/bugzilla/show_bug.cgi?id=57653



Attached is the thread dump that includes EXCEPTION_ACCESS_VIOLATION error.
Comment 1 Mark Thomas 2020-01-16 14:32:58 UTC 
Please re-test with the latest 7.0.x release (7.0.99 as I type this). The APR poller has been significantly re-factored since 7.0.94.
Comment 2 Mark Thomas 2020-03-16 13:10:23 UTC 
No updates for 2 months.

I am going to assume that the changes in the Poller between 7.0.94 and 7.0.99 addressed this issue.

If you still see this issue with the latest 7.0.x release then please feel to re-open this issue. You will need to provide the steps necessary to reproduce the issue from a clean install of the latest 7.0.x release available at that time.