On Tue, Apr 30, 2024 at 10:07 PM Tom Lane <t...@sss.pgh.pa.us> wrote:
> Ron Johnson <ronljohnso...@gmail.com> writes: > > When running stress tests on the systems (in prod, during the maintenance > > window), 171K events/second are generated on the RHEL8 servers, and CB > > needs (according to top(1)) 325% of CPU to handle that, and still > dropping > > 92% of them. > > The RHEL6 system doesn't bat an eye at running the exact same test (36 > cron > > jobs running psql executing SELECT statements). > > Is JIT enabled on the newer system? If so try turning it off, or else > raise the associated cost settings. We've seen lots of reports of > workloads where, by default, the planner is too aggressive about > applying JIT. > A puzzling suggestion. Why should it impact AV software? At one point, I disabled JIT to test its impact on PG, performance was a bit of a wash (some queries were a bit faster, some were a bit slower), but I didn't monitor CB. Just now, I did ALTER SYSTEM SET jit='off'; and re-ran the stress test. No impact to CarbonBlack.
