Thursday, October 3, 2013

RAID vs IO Calculation

RAID vs IO Calculation




counters for RAID configurations with the following calculations:
Raid 0: I/O per disk = (reads + writes) / number of disks
Raid 1: I/O per disk = [reads + (writes*2)] / 2
Raid 5: I/O per disk = [reads + (writes*4)] / number of disks
Raid 10: I/O per disk = [reads + (writes*2)] / number of disks
Here is an example of your I/O per disk for RAID 1, if we get these values from the counters:
Disk Reads/sec = 90
Disk Writes/sec = 75
The formula for I/O on a RAID-1 array is [reads + (writes*2)] / 2 or [90 + (75*2)] / 2 = 120 I/Os per disk

No comments:

Post a Comment