From: Achilleas Mantzios <achill@matrix.gatewaynet.com>
Organization: Dynacom Tankers Mgmt
To: pgsql-performance@postgresql.org
Subject: Re: Will shared_buffers crash a server
Date: Fri, 29 Apr 2011 09:48:35 +0200
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Normally under heavy load, a machine could potential stall, even seem to ha=
ng, but not crash.
And judging from your description of the situation your only change was in =
shared memory (IPC shm) usage, right?
I would advise to immediately run all sorts of (offline/online) hardware te=
sts (especially memtest86) on your machine,
before blaming postgesql for anything.

=CE=A3=CF=84=CE=B9=CF=82 Friday 29 April 2011 10:13:08 =CE=BF/=CE=B7 Qiang =
Wang =CE=AD=CE=B3=CF=81=CE=B1=CF=88=CE=B5:
> Hei:=20
>=20
>=20
> We have PostgreSQL 8.3 running on Debian Linux server. We built an applic=
antion using PHP programming language and Postgres database. There are appo=
ximatly 150 users using the software constantly. We had some performance de=
gration before and after some studies we figured out we will need to tune P=
ostgreSQL configurations.=20
>=20
>=20
> We have 10GB memory and we tuned PostgreSQL as follow:
> - max_connection =3D 100
> - effective_cache_size =3D 5GB
> - shared_buffer =3D 2GB
> - wal_buffer =3D 30MB
> - work_mem =3D 50MB
>=20
> However we suffered 2 times server crashes after tunning the configuratio=
n. Does anyone have any idea how this can happen?
>=20
> BR=20
>=20
> Kevin Wang
>=20


=2D-=20
Achilleas Mantzios