Re: Two identical systems, radically different performance - Mailing list pgsql-performance

From Marinos Yannikos
Subject Re: Two identical systems, radically different performance
Date
Msg-id 507CEB82.8040203@geizhals.at
Whole thread Raw
In response to Re: Two identical systems, radically different performance  (Craig James <cjames@emolecules.com>)
List pgsql-performance
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


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