Re: Howto Increased performace ?

Hi,

These are some settings that I am planning to start with for a 4GB RAM dual
opteron system with a maximum of 100 connections:

shared_buffers 8192 (=67MB RAM)
sort_mem 4096 (=400MB RAM for 100 connections)
effective_cache_size 380000(@8KB =3.04GB RAM)
vacuum_mem 32768 KB
wal_buffers 64
checkpoint_segments 8

In theory, effective cache size is the amount of memory left over for the OS
to cache the filesystem after running all programs and having 100 users
connected, plus a little slack.

regards
Iain
----- Original Message -----
From: "Amrit Angsusingh" <postuser(at)spr(dot)og(dot)th>
To: "Iain" <iain(at)mst(dot)co(dot)jp>
Cc: <pgsql-performance(at)postgresql(dot)org>
Sent: Monday, December 27, 2004 6:21 PM
Subject: Re: [PERFORM] Howto Increased performace ?

>
>
>>> #sort_mem = 1024 # min 64, size in KB
>>> sort_mem = 60000
>
>> I think this might be too much. You are using 60000KB _per connection_
>> here
>> = 10GB for your maximum of 180 connections.
>>
>> By comparison, I am specifiying 4096 (subject to adjustment) for a
>> machine
>> with a similar spec to yours.
>>
>> regards
>> Iain
>
> I reduced it to
> sort_mem = 8192
> If I increase it higher , what will be result I could expect.
>
> and I also reduce the
> max connection to 160
> and
> shared buffer to shared_buffers = 27853
> effective_cache_size = 81920 [what does it for?]
>
> do you think is it still too much especialy effective cache ?
>
> Thanks
> Amrit
>
> Amrit Angsusingh
> Nakornsawan,Thailand