Re: Hosted servers with good DB disk performance? - Mailing list pgsql-performance

From Greg Smith
Subject Re: Hosted servers with good DB disk performance?
Date
Msg-id alpine.GSO.2.01.0905262309320.25097@westnet.com
Whole thread Raw
In response to Re: Hosted servers with good DB disk performance?  (Scott Marlowe <scott.marlowe@gmail.com>)
List pgsql-performance
On Tue, 26 May 2009, Scott Marlowe wrote:

> Plus if you only need 4 drives or something, you can do pretty well with
> a Dell with the RAID controller turned to JBOD and letting the linux
> kernel do the RAID work.

I think most of the apps I'm considering would be OK with 4 drives and a
useful write cache.  The usual hosted configurations are only 1 or 2 and
no usable cache, which really limits what you can do with the server
before you run into a disk bottleneck.  My rule of thumb is that any
single core will be satisfied as long as you've got at least 4 disks to
feed it, since it's hard for one process to use more than a couple of
hundred MB/s for doing mostly sequential work.  Obviously random access is
much easier to get disk-bound, where you have to throw a lot more disks at
it.

It wouldn't surprise me to find it's impossible to get an optimal setup of
8+ disks from any hosting provider.  Wasn't asking for "great" DB
performance though, just "good".

--
* Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD

pgsql-performance by date:

Previous
From: Scott Marlowe
Date:
Subject: Re: Hosted servers with good DB disk performance?
Next
From: Ron Mayer
Date:
Subject: Re: Hosted servers with good DB disk performance?