Re: software vs hw hard on linux

>>>>> "a" == aturner  <aturner@neteconomist.com> writes:

a> you need a good size cache too.  If you don't have it, RAID 5
a> performance will suck big time.  If you need speed, RAID 10 seems
a> to be the only way to go, but of course that means you are gonna
a> spend $$s on drives and chasis.  I wish someone would start a

I disagree on your RAID level assertions.  Check back about 10 or 15
days on this list for some numbers I posted on restore times for a 20+
GB database with different RAID levels.  RAID5 came out fastest
compared with RAID10 and RAID50 across 14 disks.  On my 5 disk system,
I run RAID10 plus a spare in preference to RAID5 as it is faster for
that.  So the answer is "it depends". ;-)

Both systems use SCSI hardware RAID controllers, one is LSI and the
other Adaptec, all hardware from Dell.

But if you're budget limited, spend every last penny you have on the
fastest disks you can get, and then boost memory.  Any current CPU
will be more than enough for Postgres.

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