Further Information

Performance Considerations

If you suspect that the sustained data flow to the tape device is too low or that the device does not handle it correctly, you can simulate a very fast device on the Media Agent client by doing the following:

1.Create a standalone file device and a device file /dev/null on UNIX and nul on Windows.

2.Create a separate pool and select loose policy.

3.Set InitOnLoosePolicy=1 and set data protection to None. Perform backups to this device and check if the performance discrepancy between backups to the file device and backups to the real device can be explained.You can also run the vbda locally and write directly to a file. Run the commands listed below:

On HP-UX and Solaris:

/opt/omni/lbin/vbda -vol /home -trees /home/jdo - out /dev/null -profile

On Windows:

<Data_Protector_home>\bin\vbda -vol /C -trees "/Program Files/OmniBack/bin" -out nul -profile

On Novell NetWare:

load sys:usr\omni\bin\hpvbda.nlm -vol /sys -tree /usr/omni -out \tmp\test

•Device configuration

Adjust the device block size if necessary.

•CRC option

CRC option impacts performance due to the CRC calculation, which is performed by the Media Agent client.

•Logging and Report Level

If an update of the IDB takes too long, disable logging by setting it to Log None. The same way you can filter messages by setting the Report level to Critical.

•Data Protector Application Clients

If a restore session of the Application clients (Oracle, SAP R/3) takes too long, decrease the SmWaitforNewClient value, which is by default 5 minutes. Set it to a lower value.

Appendix A

A-13