Great info to learn on determining IOPS required for Horde
Determining disk drives if you know the IOPS required If you can make an estimate of how many I/O's Per Second (IOPS) you need you can determine how many disks you'll need as RAID10 and how many disks you'll need as RAID5. Generally, a single disk drive can do this many IOPS per disk: 15k rpm: 180-210 IOPS 10k rpm: 130-150 IOPS 7200 rpm: 80-100 IOPS 5400 rpm: 50-80 IOPS In a mirrored configuration: Disk IOPS = Read IOPS + (2 * Write IOPS) In a parity (RAID5) configuration: Disk IOPS = Read IOPS + (4 * Write IOPS) Example calculations Now let's look at an example. If you estimate that you need to support 40 Read IOPS (40 reads/sec) and 80 Write IOPS (80 writes/sec). If you want to use a mirrored configuration of drives: Disk IOPS = Read IOPS + (2 * Write IOPS) = 40r/s + (2 * 80w/s) = 200 Disk IOPSUsing 7200 rpm drives, you need: 200 / 50 = 4 disk drives Using 10k rpm drives, you need: 200 / 130 = 2 disk drives (always round up) If you want ...