2009/8/3 Scott Marlowe <scott.marlowe@xxxxxxxxx> > > On Mon, Aug 3, 2009 at 10:15 AM, Brian Modra<brian@xxxxxxxxxxxxx> wrote: > > Hi, > > my database is hit with constant inserts to 6 main tables (200 inserts > > per minute to one of the tables, less to the others), some updates, > > but then the selects: > > - large retrievals of randomly different sections of the database > > (indexed maps by postgis). This data is static. > > - medium sized retrievals of the same tables that are receiving the > > inserts. By mediou sized, I mean typically 200 rows at once. These > > retrievals are also randomly different to each other, and typically > > retrieving the newly inserted data rather than the more historical. > > The database size is about 300GB and growing. > > > > What sort of hardware config would you advise? > > I'm thinking of 2x300GB SATA RAID 0 for the OS and application files, > > Is there a valid reason you're NOT considering RAID-1 here? I hope > RAID-0 is a typo. It was an error. I wanted mirroring. But... on second thoughts, is there really a good reason for using a second set of disks for the OS? Once the database is running, its surely not going to be using the OS disk much, so why not just make a big RAID 10 array and use that for both OS and DB... partition it as usual I mean - boot, root. Should I use another disk for swap... for that matter, do I need swap at all... RAM with be at least 16GB? > > > and 6x300GB SAS RAID 10 for the database... but some experts have said > > RAID 5 is fine. I'm inlined to think RAID 10, but I'm not an expert. > > Your advice will be much appreciated. > > Then I question the expertise of your experts. RAID5 is not fine. > It's slow, more prone to loss due to drive loss, and generally not a > good choice for databases. > > I would gladly have more SATA drives in a RAID-10 than fewer SAS > drives in a RAID-5. > > if someone is worried about "wasting" disk space tell them to worry > about something else, like losing data. -- Brian Modra Land line: +27 23 5411 462 Mobile: +27 79 69 77 082 5 Jan Louw Str, Prince Albert, 6930 Postal: P.O. Box 2, Prince Albert 6930 South Africa http://www.zwartberg.com/ -- Sent via pgsql-admin mailing list (pgsql-admin@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
