Re: Ideal Hardware?

On Wed, 1 Oct 2003, Jason Hihn wrote:

> We have an opportunity to purchase a new, top-notch database server. I am
> wondering what kind of hardware is recommended? We're on Linux platforms and
> kernels though.
[...]
> The configuration that is going on in my head is:
> RAID 1, 200gig
> 1 server, 4g ram
> Linux 2.6

I vaguely remember someone (Tom?) mentioning that one of the log
files probably might want to go on its own partition.  Sometime in
the last 2 weeks.  I am not pushing dbase stuff here, but my
system is about your size.  About 120 GB of my disk is RAID
on a promiseware card, using the kernel software RAID (apparently
software RAID on Linux is faster than the promisecard does it
in hardware).  I have a bunch of different things using software
RAID:
 /tmp is a RAID 0 with ext2
 /home is a RAID 5 with ext3
 /usr, /var, /usr/local is RAID 10 with ext3
 /var/lib/postgres is on a real SCSI 10k, on ext3 with noatime

So, my postgres isn't on the RAID(s).  I just got finished
rebuilding my RAIDs for the second time (failed disk).  I ended
up rebuilding things in single user mode, so I can't set tasks in
parallel.  I don't know if you can do this in multi-user mode
and/or in parallel.  I'm being paranoid.  Rebuilding RAID 5 is
fast, rebuilding RAID 1 is a pain in the butt!  My biggest RAID 10
is about 10 GB, bundling the new partition from the new disk into
the RAID 0 is fast, rebuilding the mirror (RAID 1 part) takes 10
hours!  Dual athlon 1.6's and 1 GB of RAM, so I have lots of
horsepower.  Maybe you are going with better RAID than I have,
but it seems to me that RAID 5 (with spares) is going to be better
if you ever have to rebuild.

Gord