Even though 5.19.11 ran okay on four busy servers for a week, 5.19.12 is NOT running well, and 5.19.11 is no longer available so I’m going to go back to a stock 5.15 Ubuntu kernel on most of the machines.  Tonight there will be additional reboots between 11pm-11:30pm to this end.

     It seems to me that some fundamental change was made to the Linux kernel in 5.16 and forward that greatly improved scheduling and context switching efficiency but introduced serious stability problems that are not yet addressed.  So at this point I’m going back to a stock 5.15 kernel and when the official release of 6.0 comes out we’ll experiment with that.  I may also experiment with some custom configurations of 5.15 to see if we can’t improve the scheduling and context switching efficiency of that kernel somewhat.