Re: Troubleshooting a brief spike in active sessions
Nikolay Samokhvalov <nik@postgres.ai>
From: Nikolay Samokhvalov <nik@postgres.ai>
To: "Dirschel, Steve-CW" <Steve.Dirschel@bestbuy.com>
Cc: "pgsql-performance@lists.postgresql.org"
<pgsql-performance@lists.postgresql.org>
Date: 2026-01-09T22:29:20Z
Lists: pgsql-performance
BTW, what are you logging settings for slow queries? (log_min_duration_statement, auto_explain.log_min_duration) On Fri, Jan 9, 2026 at 2:27 PM Nikolay Samokhvalov <nik@postgres.ai> wrote: > On Fri, Jan 9, 2026 at 1:41 PM Dirschel, Steve-CW < > Steve.Dirschel@bestbuy.com> wrote: > > > > Aurora Postgres version 17.4 > > > > ... > > > > The app sessions will show as wait_event_type and wait_event as null > which I understand means they are on CPU > > > > ... > > > Not necessarily. It also might be an uninstrumented wait event. > > Do the spikes of "CPU" AAS (I prefer to call them "CPU*") correspond well > to the spikes of high usage? > > If you have N active sessions marked as CPU in ASH, does it match to the > CPU load of similar scale? > > If the VM has much less than 400 vCPUs and you see overall CPU load far > from 100%, then we should suspect some missing wait event. > > Nik >