Re: Metrics api calls causing blocking threads during indexing

[Shawn Heisey]

On 7/11/23 06:24, michael dürr wrote:
I recently observed that calls to the metrics api get stuck (thread state
waiting) when we call it for an index that is built from scratch. This
became a problem when we used the solr metrics exporter and unexpectedly
ran out of memory due to the accumulating threads.
This is one of the waiting thread's stacktrace (collected by the
solr/admin/info/threads
endpoint):

{
   "id": 28,
   "name": "qtp2085745483-28",
   "state": "WAITING",
   "lock": "java.lang.Object@6665e80c",

This thread is waiting for the lock on 'java.lang.Object@6665e80c' to be 
released.  You would need to look through the rest of the threads to see 
what thread is holding that lock, then we need the exact version of Solr 
you're running and the stacktrace of that thread so we can look at the 
source code to see what might be wrong.

If you are running a customized version of Solr that was compiled from 
source, it might be necessary to have access to the customized source code.

Thanks,
Shawn