From: Justin Graf <justin@magwerks.com>
To: =?utf-8?Q?_Grzegorz_Ja=C5=9Bkiewicz_ <gryzman@gmail.com>
Cc: postgres performance list <pgsql-performance@postgresql.org>
Subject: Re: raid10 write performance
Date: Tue, 22 Jun 2010 08:40:03 -0500
Message-ID: <4C20BD33.1040908@magwerks.com> (raw)
In-Reply-To: <AANLkTinbKXufTYhNuhNaOW2kWM-simIL3dg0uFX7Ij6g@mail.gmail.com>
References: <AANLkTinbKXufTYhNuhNaOW2kWM-simIL3dg0uFX7Ij6g@mail.gmail.com>
On 6/22/2010 4:31 AM, Grzegorz Jaśkiewicz wrote:
> Hi folks,
>
> is there a general problem with raid10 performance postgresql on it?
> We see very low performance on writes (2-3x slower than on less
> performant servers). I wonder if it is solely problem of raid10
> configuration, or if it is postgresql's thing.
>
RAID 10 is the commonly suggested layout for DB's as its performance to
redundancy is good.
The question that begs to be ask is what is the IO layout on the other
servers your comparing against.
> Would moving WAL dir to separate disk help potentially ?
>
Yes it can have a big impact.
http://www.westnet.com/~gsmith/content/postgresql/TuningPGWAL.htmhttp://wiki.postgresql.org/wiki/Performance_Analysis_Toolshttp://wiki.postgresql.org/wiki/Performance_Optimization> We're running centos 5.4, and server config is:
>
> x3550 M2, xeon 4c e5530 2.4ghz , 6GB of ram
> disks: ibm 300gb 2.5 SAS
>
> raid: serveRAID M5014 SAS/SATA controller
>
> strip size is the default 128k
>
>
> thanks.
>
>
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To: pgsql-performance@postgresql.org
Cc: justin@magwerks.com, gryzman@gmail.com
Subject: Re: raid10 write performance
In-Reply-To: <4C20BD33.1040908@magwerks.com>
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