Re: how to partition disks

Hi Hupert,

hubert depesz lubaczewski schrieb:
> On 6/14/06, *Sven Geisler* <sgeisler(at)aeccom(dot)com
> <mailto:sgeisler(at)aeccom(dot)com>> wrote:
> You should configure your discs to RAID 10 volumes.
> You should set up a separate volume for WAL.
> A volume for an additional table space may also useful.
> In your case I would do 2 partitions:
> 1. RAID 10 with 8 discs for general data
>
>
> raid 10 is of course not questionable. but are you sure that it will
> work faster than for example:
> 2 discs (raid 1) for xlog
> 6 discs (raid 10) for tables
> 6 discs (raid 10) for indices?
>

This depends on your application. Do you have a lot of disc reads?
Anyhow, I would put the xlog always to a RAID 10 volume because most of
the I/O for update and inserts is going to the xlog.

4 discs xlog
6 discs tables
4 discs tables2

This should be better. You should distribute indices on separate spindle
stacks to share the I/O. But again this depends on your application and
your server. How are the indices used? How large is your file system
cache. What does PostgreSQL effectively read from disc.

Don't forget to tune your postgresql.conf:
<http://www.powerpostgresql.com/PerfList>
<http://www.powerpostgresql.com/Downloads/terabytes_osc2005.pdf>

Cheers
Sven.