Performance factors for HP ProLiant Serial Attached Storage (SAS)

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Figure 14. Performance comparison: 10K versus 15K RPM, RAID 5 controller and 6 SFF SAS drives
As indicated by the charts, 15K drives show a significant advantage where the requested data blocks
are stripe size (64 KB) or larger. Although the IOPS rating can increase with greater queue depths,
the system is best when the queue depth remains below 32.
Figure 15 below compares the random read performance of 10K and 15K SFF SAS drives for arrays
of three to eight drives, using RAID 5 with the stripe size set to 128 KB.
A: Sequential read, Q1 B: Sequential read, Q4
C: Sequential read, Q8
D: Sequential read, Q16
E: Sequential read, Q32 F: Random IOPS
10K RPM
SAS
HDD
15
K RPM
SAS
HDD
MiB/s
Mib/s
MiB/s
MiB/s
MiB/s
IOPS