From: Luke Lonergan <llonergan@greenplum.com>
To: Rajesh Kumar Mallah <mallah.rajesh@gmail.com>
To: pgsql-performance@postgresql.org
Subject: Re: setting up raid10 with more than 4 drives
Date: Tue, 29 May 2007 14:50:57 -0700
Message-ID: <C281EE51.31A7F%llonergan@greenplum.com> (raw)
In-Reply-To: <a97c77030705291414t115644ecr6f9a812c0e7c56bf@mail.gmail.com>
Stripe of mirrors is preferred to mirror of stripes for the best balance of
protection and performance.
In the stripe of mirrors you can lose up to half of the disks and still be
operational. In the mirror of stripes, the most you could lose is two
drives. The performance of the two should be similar - perhaps the seek
performance would be different for high concurrent use in PG.
- Luke
On 5/29/07 2:14 PM, "Rajesh Kumar Mallah" <mallah.rajesh@gmail.com> wrote:
> hi,
>
> this is not really postgresql specific, but any help is appreciated.
> i have read more spindles the better it is for IO performance.
>
> suppose i have 8 drives , should a stripe (raid0) be created on
> 2 mirrors (raid1) of 4 drives each OR should a stripe on 4 mirrors
> of 2 drives each be created ?
>
> also does single channel or dual channel controllers makes lot
> of difference in raid10 performance ?
>
> regds
> mallah.
>
> ---------------------------(end of broadcast)---------------------------
> TIP 9: In versions below 8.0, the planner will ignore your desire to
> choose an index scan if your joining column's datatypes do not
> match
>
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-performance@postgresql.org
Cc: llonergan@greenplum.com, mallah.rajesh@gmail.com
Subject: Re: setting up raid10 with more than 4 drives
In-Reply-To: <C281EE51.31A7F%llonergan@greenplum.com>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox