HP Data Protector Software Performance White Paper

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Disk read performance
The disk read performance was determined for HP-UX with L&TT, and for Windows with the
HPReadData utility.
Figure 29 demonstrates that multiple reads (five streams from five disk volumes) perform much
better than single reads (one stream from one disk volume). With Windows, single reads of
small files (4 – 16 KB) are very slow because the NTFS file system overhead is much higher
than with HP-UX VxFS.
Figure 29. Results of disk read tests
Note: The performance data of parallel reads is determined by the data volume divided by the
time of the slowest read process. This approach simulates a backup application which does not
finish until the last byte is read.
Disk Read Performance
Typical and Millions of Small Files
105
262
266
11
53
24
29
131
0.00
50.00
100.00
150.00
200.00
250.00
300.00
Typical Single Windows
Typical Parallel Windows
Typical Single HP-UX
Typical Parallel HP-UX
Small Single Windows
Small Parallel Windows
Small Single HP-UX
Small Parallel HP-UX
MB/s