Core threads in EnhancedQueueExecutor might timeout below core pool size even if allowCoreTimeOut is false

[dmlloyd]

I can see unexpected behavior in EnhancedQueueExecutor [1]. Even when I set allowsCoreThreadTimeOut to false, sometimes happens that pool size goes below core size by a few threads.

Test scenario:

• create EnhancedQueueExecutor with coreSize=3, maxSize=6, allowsCoreThreadTimeOut=false, keepAliveTimeout=1000ms
• submit 6 threads into executor and wait until all are running so maxSize is reached
• allow all threads to finish and wait some time for threads to timeout

Expected result is that poolSize will be 3 as coreSize=3 but sometimes happens that poolSize is 2 or 1.

This might not be a bug as EnhancedQueueExecutor estimates its pool size and might allow to timeout more threads than coreSize. I'm creating this jira so it's explained for future reference.

[1] https://github.com/jbossas/jboss-threads/blob/2.3.3.Final/src/main/java/org/jboss/threads/EnhancedQueueExecutor.java

[2] https://issues.jboss.org/browse/EAP7-488

This issue was imported from JIRA. The original issue is JBTHR-78. It was originally reported by @mnovak1.

[dmlloyd]

It looks like the same as JBTHR-49. But JBTHR-49 was fixed in jboss-threads version 2.3.1.Final, 2.4.0.Final, and wildfly-core currently has jboss-threads version 2.3.3.Final, but still sees this problem.

This comment was imported from JIRA. It was originally authored by @chengfang.

[dmlloyd]

Should this be in JBTHR?

This comment was imported from JIRA. It was originally authored by @bstansberry.

[dmlloyd]

Yes, JBTHR-49 is fixed in 2.3.3.Final. This will be something else.

This comment was imported from JIRA. It was originally authored by @mnovak1.

[sarthaksarthak9]

hey, i would to like to solve it .. please assign this to me

[dmlloyd]

You may send in a PR even if an issue isn't assigned. I do not usually use the assignment function.