HP Data Protector Software Performance White Paper

Restore of typical and small files

This section covers local and network-based restore of typical and small files.

Local restore of typical files

The files were restored directly from the SCSI-attached Ultrium 960 tape drive.

For Windows, test 1 in Table 5 shows that the tape device did not read faster than 156.00 MB/s.

Test 3 shows that the disk device resulted in164.67 MB/s write performance and test 4 in 145.07

MB/s restore performance for Data Protector. If the performance of two devices is so close, the

tape has sometimes to wait for I/O which explains the slightly slower Data Protector

performance. Note that a disk device does not show a completely consistent performance from

the operating system’s point of view. It will always fluctuate, and monitoring tools just display the

average value in a configured timeframe. This can be verified, for example with the built-in

performance tool Perfmon for Windows.

For HP-UX, test 1 in Table 5 shows that the tape device result of 160.71 MB/s was less than the

disk device result in test 3 (193.07 MB/s). Here, the tape device was the bottleneck.

Table 5. Local restore of typical files – bottleneck determination

Test Performance (MB/s) Bottleneck?

1. Windows L&TT Tape Read

156.00

Yes (Tape)

2. Windows HPCreateData Single

133.98 No

3. Windows HPCreateData Parallel

164.67 No

4. Windows DP Ultrium 960 Parallel 145.07 No

1. HP-UX L&TT Tape Read

160.71

Yes (Tape)

2. HP-UX HPCreateData Single

166.28 No

3. HP-UX HPCreateData Parallel

193.07 No

4. HP-UX DP Ultrium 960 Parallel 153.30 No

Tested in the section Evaluating tape and disk drive performance on page 32