Message-ID: <4C575DCF.3050700@2ndquadrant.com>
Date: Mon, 02 Aug 2010 20:07:43 -0400
From: Greg Smith <greg@2ndquadrant.com>
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To: Josh Berkus <josh@agliodbs.com>
CC: pgsql-performance@postgresql.org
Subject: Re: Testing Sandforce SSD
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Josh Berkus wrote:
> That doesn't make much sense unless there's some special advantage to a
> 4K blocksize with the hardware itself.

Given that pgbench is always doing tiny updates to blocks, I wouldn't be 
surprised if switching to smaller blocks helps it in a lot of situations 
if one went looking for them.  Also, as you point out, pgbench runtime 
varies around wildly enough that 10% would need more investigation to 
really prove that means something.  But I think Yeb has done plenty of 
investigation into the most interesting part here, the durability claims. 

-- 
Greg Smith  2ndQuadrant US  Baltimore, MD
PostgreSQL Training, Services and Support
greg@2ndQuadrant.com   www.2ndQuadrant.us