Message-ID: <4E24D409.2070500@2ndquadrant.com>
Date: Mon, 18 Jul 2011 20:47:05 -0400
From: Greg Smith <greg@2ndquadrant.com>
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To: "M. D." <lists@turnkey.bz>
CC: pgsql-performance@postgresql.org
Subject: Re: cpu comparison
References: <4E248E04.2090506@turnkey.bz>
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M. D. wrote:
> I'm a bit surprised as the x3450 has DDR3, while the E5335 has DDR2, 
> and of course because of the cycle speed difference alone I would 
> think the X3450 should beat the E5335.

Try comparing them with stream-scaling to see what happens:

https://github.com/gregs1104/stream-scaling

You can't really test CPU performance in a simple way anymore; it varies 
depending on the number of processes running at once.  This test is the 
best way I've found to show how that works.  On a single thread, the 
X3450 may not be significantly better than the E5535.  But what should 
happen is that total speed keeps going up as you add more threads on the 
newer system, while the old DDR2 model stays as the same basic total.

-- 
Greg Smith   2ndQuadrant US    greg@2ndQuadrant.com   Baltimore, MD