Thread: Linux - postgres RAID

Linux - postgres RAID

From
Rick Gigger
Date:
I figure this would be a good place to ask. I want to build / buy a
new linux postgres box.  I was wondering if anyone on this list had
some experience with this they'd like to share.  I'm thinking
somewhere in the $7k - 15k range.  The post important things are
write speed to the disk and good linux driver support for the raid
card.  Can anyone recommend a specific raid card / server vendor?

Thanks,

Rick

Re: Linux - postgres RAID

From
Rick Gigger
Date:
Ok then, the size of the postgres data directory is about 1 GB.  The
OS will be a version of linux with a 2.6 kernel.  100 GB of total
storage would be plenty.  The load load would probably be around
2k-3k transactions / minute.  I plan on doing a lot of research on my
own I am just looking for a place to start looking.

On Jan 23, 2006, at 12:19 PM, Wes Williams wrote:

> For those funds you best be served by defining the database size,
> projected
> capacity, load, specific OS, and other details in order to even
> remotely
> receive a usable reply.
>
>
>
>
> -----Original Message-----
> From: pgsql-general-owner@postgresql.org
> [mailto:pgsql-general-owner@postgresql.org]On Behalf Of Rick Gigger
> Sent: Monday, January 23, 2006 2:13 PM
> To: pgsql general
> Subject: [GENERAL] Linux - postgres RAID
>
>
> I figure this would be a good place to ask. I want to build / buy a
> new linux postgres box.  I was wondering if anyone on this list had
> some experience with this they'd like to share.  I'm thinking
> somewhere in the $7k - 15k range.  The post important things are
> write speed to the disk and good linux driver support for the raid
> card.  Can anyone recommend a specific raid card / server vendor?
>
> Thanks,
>
> Rick
>
> ---------------------------(end of
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> TIP 1: if posting/reading through Usenet, please send an appropriate
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> your
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>


Re: Linux - postgres RAID

From
Steve Atkins
Date:
On Jan 23, 2006, at 11:13 AM, Rick Gigger wrote:

> I figure this would be a good place to ask. I want to build / buy a
> new linux postgres box.  I was wondering if anyone on this list had
> some experience with this they'd like to share.  I'm thinking
> somewhere in the $7k - 15k range.  The post important things are
> write speed to the disk and good linux driver support for the raid
> card.  Can anyone recommend a specific raid card / server vendor?

It'll depend on what you're planning on using it for. Performance
requirements, capacity
and so on.

For fast writes you'll probably want something like RAID10 with lots
of spindles. SCSI
is likely to be somewhat faster, but a lot more expensive. For SATA
RAID most people
like the 3ware and Areca cards. I'm using this system, from ASA, for
pretty much that
and it seems OK. 5U server, 24 external bay, 2 internal bay capacity.
And it's opterons,
which seem to be a bit more PG-friendly than Xeons. It uses the 3ware
9550SX card.
(The general opinion here seems to be that the Areca cards are
somewhat "better"
than the 3wares, but a lot more expensive).

http://www.asaservers.com/config_system.asp?config_id=5USATA

Cheers,
   Steve


Re: Linux - postgres RAID

From
Carlos Moreno
Date:
Rick Gigger wrote:

> I figure this would be a good place to ask. I want to build / buy a
> new linux postgres box.  I was wondering if anyone on this list had
> some experience with this they'd like to share.  I'm thinking
> somewhere in the $7k - 15k range.  The post important things are
> write speed to the disk and good linux driver support for the raid
> card.  Can anyone recommend a specific raid card / server vendor?


Instead of (or in addition to) RAID configurations, you may want to
consider using multiple disks, connected to independent channels
(not a problem if you're talking SATA), such that PG can perform
simultaneous access to the various filesystems.  I'm not sure which
parts are critical, or how many different partitions you would need
for optimal performance, but the "PG Performance" mailing list
archives should prove useful to find out about this.

Maybe you could use SATA Raptor drives -- the 10k RPM, which
I believe has a sustained transfer rate in the order of 80 or 90 MB/sec.

Do make sure that you get a MB with fast internal bus (533 or 800
MB/sec at least), so that you don't waste your money on multiple
independently-connected hard drives that hit a bottleneck when the
data reaches the motherboard.

And don't even bother to show up again if you were planning to
put less than 4GB of memory!!  :-)

HTH,

Carlos
--


Re: Linux - postgres RAID

From
Rick Gigger
Date:
Thanks!  That's just the sort of info I am looking for.

I am definitely going with the fastest scsi drives I can get.
Probably a 6 or 8 disk system.  Is there a huge jump between using 4
and 6 drives, or 6 and 8 drives?

On Jan 23, 2006, at 12:42 PM, Steve Atkins wrote:

>
> On Jan 23, 2006, at 11:13 AM, Rick Gigger wrote:
>
>> I figure this would be a good place to ask. I want to build / buy
>> a new linux postgres box.  I was wondering if anyone on this list
>> had some experience with this they'd like to share.  I'm thinking
>> somewhere in the $7k - 15k range.  The post important things are
>> write speed to the disk and good linux driver support for the raid
>> card.  Can anyone recommend a specific raid card / server vendor?
>
> It'll depend on what you're planning on using it for. Performance
> requirements, capacity
> and so on.
>
> For fast writes you'll probably want something like RAID10 with
> lots of spindles. SCSI
> is likely to be somewhat faster, but a lot more expensive. For SATA
> RAID most people
> like the 3ware and Areca cards. I'm using this system, from ASA,
> for pretty much that
> and it seems OK. 5U server, 24 external bay, 2 internal bay
> capacity. And it's opterons,
> which seem to be a bit more PG-friendly than Xeons. It uses the
> 3ware 9550SX card.
> (The general opinion here seems to be that the Areca cards are
> somewhat "better"
> than the 3wares, but a lot more expensive).
>
> http://www.asaservers.com/config_system.asp?config_id=5USATA
>
> Cheers,
>   Steve
>
>
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