Strange performance problem

[James_Butler_2]

Hi

I am having performance issues backing up one particular Windows 2000 server, using NBU6.0 MP3 (although this was also seen under NBU 5.1 MP3).

When I backup the client using the old Backup Exec 9.1 installation to LTO-2 drives, I manage to get 36MB/sec and backup the 300Gb data set in just under three hours.

However, when I use NetBackup, this drops to about 11MB/sec, and the backup takes eight hours.

Nothing else on the server has changed except the removal of the Backup Exec client and the installation of the Netbackup one. I can backup other clients at up to 65MB/sec to the same hardware. Virus scanning is disabled.

I have followed the performance / troubleshooting guide from Veritas, and when I run bpbkar32 -nocont s:\ > NUL I get the proper "potential" reading of 27MB/sec.

The logs don't show much, only the buffer for the tape drive waiting to be filled.

Any ideas on this one?

Thanks
James

[Chia_Tan_Beng]

Did you enable compression option in the backup policy's attribute?

[James_Butler_2]

Nope, no multiple data streams, compression, multiplexing etc., just a simple full backup policy. The performance does not change if these options are enabled or disabled, or whether it is to disk or tape.

[Stumpr2]

>The logs don't show much, only the buffer for the tape drive waiting to be filled.

so...have you tried smaller buffers with the $INSTALL_DIR\netbackup\\db\config\SIZE_DATA_BUFFERS file?