At this point I have Linux kernel 6.0 installed on all but private virtual machines and the physical hosts.  So far it’s running MUCH better than rc5 or rc6,  but not perfect.  I’ve gotten ONE expedited RCU CPU stall in a days time on a dozen or so machines.  With 6.0rc5-6 I would see dozens in the same time frame.

     The scheduler has been substantially re-worked in the 6.0 kernel, most of these changes were aimed at AMD CPUs but it made for substantial performance improvements on Intel as well.  One stall in one day across a dozen machines means one process hung for up to two minutes in that time frame, not a HUGE concern but enough that I don’t want to put it on the physical hosts yet.  The scheduling changes cut the latency for the web server down by approximately 6 fold, that ain’t chicken feed!

     I’ve posted the most recent expedited RCU CPU stall with the bug report I had filed with bugzilla.kernel.org, for anyone interested it is bug #216501 and you can read the details here: https://bugzilla.kernel.org/show_bug.cgi?id=216501.