On Thu, 28 Jul 2005 16:55:55 -0700 Mark Wong <[EMAIL PROTECTED]> wrote:
> On Thu, 28 Jul 2005 18:48:09 -0500 > "Jim C. Nasby" <[EMAIL PROTECTED]> wrote: > > > On Thu, Jul 28, 2005 at 04:15:31PM -0700, Mark Wong wrote: > > > On Thu, 28 Jul 2005 17:17:25 -0500 > > > "Jim C. Nasby" <[EMAIL PROTECTED]> wrote: > > > > > > > On Wed, Jul 27, 2005 at 07:32:34PM -0700, Josh Berkus wrote: > > > > > > This 4-way has 8GB of memory and four Adaptec 2200s controllers > > > > > > attached > > > > > > to 80 spindles (eight 10-disk arrays). For those familiar with the > > > > > > schema, here is a visual of the disk layout: > > > > > > > > > > > > http://www.osdl.org/projects/dbt2dev/results/dev4-015/layout-6.html > > > > > > > > Have you by-chance tried it with the logs and data just going to > > > > seperate RAID10s? I'm wondering if a large RAID10 would do a better job > > > > of spreading the load than segmenting things to specific drives. > > > > > > No, haven't tried that. That would reduce my number of spindles as I > > > scale up. ;) I have the disks attached as JBODs and use LVM2 to stripe > > > the disks together. > > > > I'm confused... why would it reduce the number of spindles? Is > > everything just striped right now? You could always s/RAID10/RAID0/. > > RAID10 requires a minimum of 4 devices per LUN, I think. At least 2 > devices in a mirror, at least 2 mirrored devices to stripe. > > RAID0 wouldn't be any different than what I have now, except if I use > hardware RAID I can't stripe across controllers. That's treating LVM2 > striping equal to software RAID0 of course. Oops, spindles was the wrong word to describe what I was losing. But I wouldn't be able to spread the reads/writes across as many spindles if I have any mirroring. Mark ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org
