In a Netware 6.5, sp5 server with local volumes and local tape drive. I am
running Backup Exec.

My throughput speeds on a full backup are pretty good. However a
differential backup gives me a throughput that is only about 10% of the
full backup.

I have played with tsafs /nocaching. There is no virus scanner in place.

Running the same differential backup twice in a row (thus having files
cached) gives a throughput of about 50% of a full backup.

What sort of results do others get?