It's really amazing how much solid state drives transferred the database bottleneck away from disk.
Adam – so very true. We used to spend ungodly amounts of time/money/effort to mitigate disk performance limitations. It is almost MAGIC what SSDs do now.
Real numbers don’t lie: 5400 rpm disks can muster no more than 65 IOPS (7200s get ~90-100, 10k get 140-150). So:
15 x 65 = 975 IOPS (aka boohoo)
Using the AS SSD Benchmark, the Samsung 480gb m2 850 EVO in my core i7 laptop measures (IOPS then MB/s):
Random 4k blocks: 7,235 iops read, 14,012 iops
Random 4K-64Threads: 97,743 iops read, 68,864 iops write
Random 512B: 14,380 iops read, 19,858 iops write (db comparison here)
MB/s:
Sequential: 500 MB/s read, 449 MB/s write
Random 4K: 28.26 MB/s read, 54.74 MB/s write
4K-64Threads: 381.81 MB/s read, 269.00 MB/s write (this is closer to what db access looks like).
Access Times: 0.070 ms read, 0.050 ms write
Thusly,
1 x SSD = 14.75 times faster than a 15 drive array on reads, and 20 times faster on writes.
Like everyone else has said, just buy a 1 TB Samsung EVO 850 for $300 (USD) and call it a day. J
Mike