Andrew Lentvorski wrote:
You don't want a parity striping RAID (5 or 6) if you value write performance.
Modern drives provide more than fast enough write performance for any of our apps. Writes under RAID5 on our current systems do quite well. I am about to set up a new disk node on our SAN which has 8 disks and I am seriously considering using RAID6.
NetApp can get away with it because they have nice battery-backed caches that reorder and hide the whole read-modify-write cycle required with parity striping. In addition, they have hardware accelerators to hide the XOR required to generate the parity stripe.
Due to our cool AoE infrastructure my SAN also has battery backed caches which reorder and hide the read-modify-write cycles. And it cost a whole hell of a lot less than NetApp gear. :)
-- Tracy R Reed http://ultraviolet.org A: Because we read from top to bottom, left to right Q: Why should I start my reply below the quoted text -- [email protected] http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
