Message-ID: <449AA6E9.9050804@tweakers.net>
Date: Thu, 22 Jun 2006 16:19:21 +0200
From: Arjen van der Meijden <acmmailing@tweakers.net>
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To: David Roussel <pgsql-performance@diroussel.xsmail.com>
Cc: pgsql-hackers@postgresql.org, pgsql-performance@postgresql.org
Subject: Re: [HACKERS] Sun Donated a Sun Fire T2000 to the PostgreSQL
References: <4492CBE2.3090509@sun.com> <449331EC.10207@tweakers.net>
	<200606161624.17081.josh@agliodbs.com>
	<44951A42.6060007@tweakers.net>
	<449A9533.1030103@diroussel.xsmail.com>
In-Reply-To: <449A9533.1030103@diroussel.xsmail.com>
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On 22-6-2006 15:03, David Roussel wrote:
> Sureky the 'perfect' line ought to be linear?  If the performance was 
> perfectly linear, then the 'pages generated' ought to be G times the 
> number (virtual) processors, where G is the gradient of the graph.  In 
> such a case the graph will go through the origin (o,o), but you graph 
> does not show this. 
> 
> I'm a bit confused, what is the 'perfect' supposed to be?

First of all, this graph has no origin. Its a bit difficult to test with 
less than one cpu.

Anyway, the line actually is linear and would've gone through the 
origin, if there was one. What I did was take the level of the 
'max'-line at 1 and then multiply it by 2, 4, 6 and 8. So if at 1 the 
level would've been 22000, the 2 would be 44000 and the 8 176000.

Please do notice the distance between 1 and 2 on the x-axis is the same 
as between 2 and 4, which makes the graph a bit harder to read.

Best regards,

Arjen