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Message-ID: <507CEB82.8040203@geizhals.at>
Date: Tue, 16 Oct 2012 07:07:14 +0200
From: Marinos Yannikos <mjy@geizhals.at>
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To: pgsql-performance@postgresql.org
Subject: Re: Two identical systems, radically different performance
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On 15.10.2012 17:01, Craig James wrote:
>>>> On Thu, Oct 11, 2012 at 11:14 AM, Andrea Suisani <sickpig@opinioni.net>
>>>> wrote:
>>>>> I've googled a bit and I've found a way to disable hyperthreading
>>>>> without
>>>>> the need to reboot the system and entering the bios:
>>>>>
>>>>> echo 0 >/sys/devices/system/node/node0/cpuX/online

A safer method is probably to just add the "noht" kernel boot option and
reboot.

Did you set the same stride / stripe-width values on your FS when you
initialized them? Are both really freshly-made ext4 FS and not e.g. the
old one an ext3 mounted as ext4? Do all the disks have the same cache,
link speed and NCQ settings (for their own caches, not the controller;
try /c0/p0 show all etc. with tw_cli)?

-mjy