On Tue, Jun 09, 2020 at 01:54:21PM +0200, Krzysztof Olszewski wrote: > I had hugepage's off and on, problems still occurs, > thanx for "perf top" suggestion, > pt., 5 cze 2020 o 13:38 Pavel Stehule <pavel.stehule@xxxxxxxxx> napisał(a): > > pá 5. 6. 2020 v 12:07 odesílatel Krzysztof Olszewski <kolszew73@xxxxxxxxx> napsal: > > > >> I have problem with one of my Postgres production server. Server works > >> fine almost always, but sometimes without any increase of transactions or > >> statements amount, machine gets stuck. Cores goes up to 100%, load up to > >> 160%. When it happens then there are problems with connect to database and > >> even it will succeed, simple queries works several seconds instead of > >> milliseconds.Problem sometimes stops after a period a time (e.g. 35 min), > >> sometimes we must restart Postgres, Linux, or even KVM (which exists as > >> virtualization host). > >> > >> My hardware > >> 56 cores (Intel Core Processor (Skylake, IBRS)) > >> 400 GB RAM > >> RAID10 with about 40k IOPS > >> > >> shared_buffers 64000 MB > >> > >> In correlation with stucks i see informations in kernel log about > >> NMI watchdog: BUG: soft lockup - CPU#25 stuck for 23s! [postmaster:33935] > > > > https://www.postgresql.org/message-id/CAHyXU0yAsVxoab2PcyoCuPjqymtnaE93v7bN4ctv2aNi92fefA%40mail.gmail.com > > > > Can be interesting a reply on Merlin's question from mail/. > > > > cat /sys/kernel/mm/redhat_transparent_hugepage/enabled > > cat /sys/kernel/mm/redhat_transparent_hugepage/defrag try this: echo 2 |sudo /sys/kernel/mm/ksm/run https://www.postgresql.org/message-id/20170718180152.GE17566%40telsasoft.com -- Justin
