Re: Tuning PostgreSQL

>>>>> "AP" == Alexander Priem <ap@cict.nl> writes:

AP> Hmmm. I keep changing my mind about this. My Db would be mostly
AP> 'selecting', but there would also be pretty much inserting and
AP> updating done. But most of the work would be selects. So would
AP> this config be OK?

I'm about to order a new server.  I haven't decided exactly how many
disks I will get, but my plan is to get an 8-disk RAID10 with 15k RPM
drives.  I don't need the volume, just the speed and number of
spindles, so I'm buying the smallest drives that meet my speed
probably 18Gb each (sheesh! I remember getting my first 5Mb disk for
my 8088 PC in college and thinking that was too much space).

My mix is nearly even read/write, but probably a little biased towards
the reading.

This machine is replacing a 5-disk box that was switched from RAID5 to
4-disk RAID10 for data plus one system disk in January (what a pain
that was to re-index, but that's another story).  The switch from
RAID5 to RAID10 made an enormous improvement in performance.  The
speedup wasn't from recreating the database:  It was restored from a
file-level backup so the actual files were not compacted or secretly
"improved" in any way, other than my occasional reindexing.

So I think your 6-disk RAID10 will be good.

--
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Vivek Khera, Ph.D.                Khera Communications, Inc.
Internet: khera@kciLink.com       Rockville, MD       +1-240-453-8497
AIM: vivekkhera Y!: vivek_khera   http://www.khera.org/~vivek/