HP Data Protector Software Performance White Paper

Network backup of small files

The small files were saved via the network (Gigabit Ethernet) to the remote backup server and

its SCSI-attached Ultrium 960 tape drive.

Table 4 shows that file systems with millions of small files were not able to fully use the remote

Ultrium 960 tape drive with the network (Gigabit Ethernet) limit of 120 MB/s. The file systems

were the bottleneck for both operating systems.

Note: For Windows tests 4 and 5, the first file system tree walk was disabled which improved

the overall performance. Without this, the performance would have been even worse.

Table 4. Network backup of small files – bottleneck determination

Test Performance

(MB/s)

CPU Load

Client

CPU Load

Backup Server

Bottleneck?

1. Windows L&TT Tape Write

154.00 - - No

2. Windows HPReadData Single

10.59 - - No

3. Windows HPReadData Parallel

29.02 - - No

4. Windows DP NULL Parallel 22.02 3% 62%

Yes (Network)

5. Windows DP Ultrium 960 Parallel 22.25 3% 62%

Yes (Network)

1. HP-UX L&TT Tape Write

158.54 - - No

2. HP-UX HPReadData Single

24.41 - - No

3. HP-UX HPReadData Parallel

53.08 - - No

4. HP-UX DP NULL Parallel 49.22 32% 21%

Yes (Network)

5. HP-UX DP Ultrium 960 Parallel 48.89 31% 21%

Yes (Network)

Recommendation: Parallel backups with a higher concurrency are recommended for file systems

with millions of small files – also if you are backing up via the network (Gigabit Ethernet). These

kinds of file systems are very slow and should be multiplexed. In the case of the fast Ultrium 960

tape drive and Gigabit Ethernet, you could consider a slower Ultrium tape drive or backup-to-

disk technology.

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