...
This idea proposes that the increased system CPU usage on the MDS is caused by RHEL7 but more spcificly Lustre-2.10. In the 1-year CPU graph of aocmds you can clearly see a large increase in system time starting around mid October 2019. There is a very similar increase in user/system CPU time on nmpost061 through nmpost070.
These are the 10 newest nodes installed for VLASS in September 2019 and started off as RHEL7/Lustre-2.10.
...