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Figure 8 compares the random read performance of 10K and 15K SFF SAS drives for arrays of three
to eight drives, using RAID 5 with the block size set to 128 KB.
Figure 8.
Random read performance: 10K versus 15K RPM SFF SAS drives, RAID 5
As indicated in Figure 8, 15K drive arrays consistently provide higher random read IOPS than 10K
drive arrays. Also, overall performance scales with array size (number of drives). Note that
performance is best when retrieving data blocks that are larger than the RAID 5 stripe size (128 KB in
this case). For optimum performance, the stripe size should be configured for the specific application.
2500
2000
1500
1000
500
IOPS
No. of drives
10K HDD & P400 controller
15K HDD & 6402 controller
4 KB Random Read
64 KB Random Read
512 KB Random Read
3 4 5 6 7 8
3 4 5 6 7 8
3 4 5 6 7 8
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