From: Hannes Dorbath <light@theendofthetunnel.de>
Subject: Re: 8.3 synchronous_commit
Date: Tue, 22 Jan 2008 13:13:57 +0100
Organization: Hub.Org Networking Services
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To: Greg Smith <gsmith@gregsmith.com>
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To: pgsql-performance@postgresql.org

Greg Smith wrote:
> Try something more in the range of 4 clients/CPU and set the scale to 
> closer to twice that (so with a dual-core system you might do 8 clients 
> and a scale of 16).  If you really want to simulate a large number of 
> clients, do that on another system and connect to the server remotely.

With 4 clients and scale 10 I get 246 TPS for synchronous_commit 
disabled and 634 TPS for synchronous_commit enabled. So the effect just 
got even stronger. That was for CFQ.

For deadline they are now pretty close, but synchronous_commit disabled 
is still slower. 690 to 727.

Values are AVG from 3 runs each. DROP/CREATE DATABASE and CHECKPOINT; 
before each run.


-- 
Best regards,
Hannes Dorbath