Re: Service outage: each postgres process use the exact amount of the configured work_mem

On Fri, Apr 14, 2017 at 10:12 AM, Moreno Andreo <moreno(dot)andreo(at)evolu-s(dot)it>
wrote:

> Hi all,
> About 2 hours and half ago, suddenly (and on the late afternoon of the
> Easter Friday), customers reported failing connections to our server, or
> even very slow.
> After a bit of checking (that also involved server reboot) I noticed
> (using top) that every process regarding postgres is using exactly the
> amout I configured as work_mem (3 GB). And AFAIK it's not good.
>
> 30085 postgres 20 0 *3370048* 156656 153876 S 6.7 0.3 0:00.20 postgres
> 29833 postgres 20 0 *3370000* 65260 62416 S 1.7 0.1 0:00.17 postgres
> 29632 postgres 20 0 *3372468* 11712 6028 S 0.7 0.0 0:00.60 postgres
>

They are all sharing the same shared_buffers (not work_mem), and that
shared space is being listed for each one of them.

This is unlikely to be related to your current problems. Nothing shown in
that output is alarming.

> What can be happened?
>

What error messages are the customers getting when they fail to connect?
What error messages are showing up in the server log file? What do you see
in pg_stat_actvity?

Cheers,

Jeff