Message-ID: <480F0C92.8050907@transporeon.com>
Date: Wed, 23 Apr 2008 12:16:50 +0200
From: =?ISO-8859-2?Q?Gerd_K=F6nig?= <koenig@transporeon.com>
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To: pgsql-admin@postgresql.org
Subject: confused of buffers and memory settings
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Hi,

we're quite new to Postgres and we're going to start using Postgres8.3 
on Opensuse10.3 64 bit. We have a dedicated dbserver with 8GB RAM, and 
now I'm not sure how to deal with the memory/buffer settings. The db 
will be accessed heavily (~20 requests/sec.) with a read/write ration of 
50:50, yes, a lot of write activity.

I thought of setting "shared_buffers" to 750000 (~6GB) but how depends 
this on the kernel buffer setting in /etc/sysctl.conf (what is the 
interaction between these two settings?).
I know the variable "shmmax" can be defined, but currently there's no 
such entry.

The meaning of "work_mem" / "maintenance_work_mem" and "wal_buffers" is 
also not clear. The maintenance_work_mem influences the size of the WAL 
logs..?!?

What else are "top performance related" options for the usage scenario I 
described earlier ?

any help appreciated....GERD...