Gord,
> I vaguely remember someone (Tom?) mentioning that one of the log
> files probably might want to go on its own partition.
That's general knowledge, but not really applicable to a fast RAID system.
It's more imporant to regular-disk systems; with 4+ disk RAID, nobody has
been able to demonstrate a gain from having the disk separation.
> 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.
Also depends on the number of disks, the controller, and the balance of read
vs. write activity. I've found RAID 5 with no cache to be dog-slow for OLTP
(heavy write transaction) databases, and use RAID 1 for that.
--
-Josh Berkus
Aglio Database Solutions
San Francisco
