In the last episode (Mar 10), John G. Heim said: > I have read (and have been told) to stay away from RAID-5 for > update-intensive systems. Are there performance concerns with RAID-10 as > well? We will be buying from Dell (done deal for reasons too complicated > to go into) and the disks they're selling are 146 Gb. I can get up to 8 > of them in the server we're buying. I asked them about just getting 2 big > disks and going with RAID-1. > > My understanding is that with RAID-10, the system can do multiple reads and > writes simultaneously so throughput is improved oversystems w/o RAID or with > RAID-1. But the same logic would apply to RAID-5 only it doesn't work out > that way.
RAID-5 has an extra penalty on small random writes due to the I/O required to maintain the parity blocks (it does 2 reads and 2 writes for every write your app does). RAID-10 is just a mirror so it doesn't have to worry about that. -- Dan Nelson dnel...@allantgroup.com -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/mysql?unsub=arch...@jab.org