RE: Public opinion on RAID 50

Hi As far as I know, Raid 50 is a RAID 5 mirrored to a RAID 5. RAID5 is slow in writes and can cause a IO bottleneck on DB reads/writes, depending where your DATA is. Go for RAID 10 or RAID 1, or let INFORMIX do the mirror for U. As far as I know, INFORMIX will spawn 2 threads to read from both the primary and the mirror, but on a write it will first write the primary then the secondary. Some RAID controllers will only read from the secondary when the primary is offline. Search for articles on RAID and INFORMIX. Art had some good ones a while back. Do not stripe more disks together, than the max Data/s your backplane/bus can handle. Test with every config. E.g.. Test performance on one disk, say you get sustained 40 Meg/s Now Stripe 2 Disks together, say you get sustained 80 Meg/s Now Stripe 3 Disks together, say you get sustained 120 Meg/s Now Stripe 4 Disks together, still you get sustained 120 Meg/s No use to stripe more than 3 disks together. {Please note that this is platform depended} Also test for IO/s. Get a copy of pfread.sh. It will determine the max number of DBSPACES you should create on one stripeset. Hope it helps Hannes Visagie Systems Engineer MIBCO -----Original Message----- From: dins dins [SMTP:dins_d@yahoo.com] Sent: Friday, March 24, 2000 10:17 AM To: informix-list@iiug.org Subject: Public opinion on RAID 50 Would this be good for Informix? How do you think? Dins __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com