Re: Tuning Linux for Postgresql - Database failed to start

Hello,

Thanks a lot for your inputs.

I only changed the section related to HugePages.

This server has 4 GB RAM.

shared_buffers = '1GB'
vm.nr_hugepages=650

tuned profile:

[main]
summary=Tuned profile for EDB PostgreSQL Instances
[bootloader]
cmdline=transparent_hugepage=never
[cpu]
governor=performance
energy_perf_bias=performance
min_perf_pct=100
[sysctl]
vm.swappiness = 10
vm.dirty_expire_centisecs = 500
vm.dirty_writeback_centisecs = 250
vm.dirty_ratio = 10
vm.dirty_background_ratio = 3
vm.overcommit_memory=0
net.ipv4.tcp_timestamps=0

[vm]
transparent_hugepages=never
vm.nr_hugepages=605

On Tue, 10 May 2022 at 22:29, Scott Ribe <scott_ribe(at)elevated-dev(dot)com>
wrote:

> > On May 10, 2022, at 2:23 PM, Albin Ary <albinary10(at)gmail(dot)com> wrote:
> >
> > Hello,
> > I have a Postgresql Database cluster.
> > Version: 14.2
> > OS: Oracle Linux 8
> >
> > I tried to follow the link to optimize the server.
> >
> https://www.enterprisedb.com/blog/tuning-red-hat-enterprise-linux-family-postgresql
> >
> > Unfortunately, after rebooting the database is not starting anymore. I
> know the HINT is straightforward but I am not able to see what the reason
> could be.
> >
> > Any advice would be appreciated.
> >
> > -- Unit postgresql-14.service has begun starting up.
> > May 10 22:10:40 postgersdb.localdomain postmaster[1612]: 2022-05-10
> 22:10:40.047 CEST [1612] FATAL: could not map anonymous shared memory:
> Cannot allocate memory
> > May 10 22:10:40 postgersdb.localdomain postmaster[1612]: 2022-05-10
> 22:10:40.047 CEST [1612] HINT: This error usually means that PostgreSQL's
> request for a shared memory segment exceeded available memory,>
> > May 10 22:10:40 postgersdb.localdomain postmaster[1612]: 2022-05-10
> 22:10:40.048 CEST [1612] LOG: database system is shut down
> > May 10 22:10:40 postgersdb.localdomain systemd[1]:
> postgresql-14.service: Main process exited, code=exited, status=1/FAILURE
> > May 10 22:10:40 postgersdb.localdomain systemd[1]:
> postgresql-14.service: Failed with result 'exit-code'.
> > -- Subject: Unit failed
> > -- Defined-By: systemd
> > -- Support: https://support.oracle.com
>
> This is a decent quick guide to the parameters affecting this:
>
> https://docs.oracle.com/cd/E19879-01/821-0182/fxxua/index.html
>
> And here is the explanation as to how they related to postgres:
>
> https://www.postgresql.org/docs/14/kernel-resources.html
>
>