Optimizing Tape Restore

[Tom O'Toole]

Do your disks have millions of little files? I haven't experienced the performance problem you speak backing up volumes with a few large database files, but I could see it getting worse with really a lot of files.

Have you done any analysis to find the bottleneck? How big is your destination disk group. What queue lengths etc are you seeing...

I am still having a hard time with how an IO limit of 8 is a good limit for backup. My experience with eva arrays are that total throughput increases with number of outstanding IOs well past 8, but admittedly that is with a different workload than backup

[Wim Van den Wyngaert · Accepted solution]

Just did a test and found no overhead for high water marking.

You could mount the disk with /nocache to avoid overhead of putting the data in the cache. Also disable disk quotas. No test data because no test disks.

Wim