There have been several hangs observed in Evergreen when running on the suse12-large distro related to pthread_mutex_lock waiting to acquire a mutex which the core dump reports as not being owned by any thread. It is strongly suspected to be an issue with the platform itself given that we haven't observed similar hangs on any other Linux distro. This has led to duplicative effort across multiple subteams to diagnose what are ultimately believed to be false positives and has led to an increase in distrust of server hangs reported on SLSE 12 in general.
We appear to be running tests on SLES 12 (SP0) which has been unsupported since 01 July 2019. SLES 12 SP3 appears to be the oldest currently supported release of SLES 12. https://www.suse.com/lifecycle
My understanding is that we intentionally compile on unsupported versions to avoid breaking our minimum supported version. This doesn't mean we must also test on those same unsupported versions, especially when there is evidence to suggest that an issue exists with the platform itself. My request is that we run server tests on a newer SLES 12 service pack in hopes it addresses the pthread_mutex_lock issues we've seen.