12.5/r15 on W2k8 R2: ? about disk activity before backup

[alpha9er]

Whenever I run a backup to tape (default settings except verification is on) with ARCserve on W2k8 R2, there is a period of HDD activity before the backup starts which takes far longer than the writing to tape part of the backup. I'm in a purely testing environment; my interest is only in seeing how the software interacts with the tape drive.

I'd like to know if there is a way to prevent this pre-write activity from occuring. Barring that, it would be helpful to have some idea what the activity is or what it's called so I can have better luck seeking it out on my own.
Thanks.

 

[davidmichel]

I've not experienced this problem on either of my W2K8 systems or heard of anyone else mentioning it.

Try checking Disable File Estimate under Global Options, Operation. There is a calculate before backup that always takes place but I've never seen it take anywhere near as long as the backup. But then for all we know you could be backing up 10mb and so overheard for the job is much more.

If the database is local then there will be updates to that, some logs get updated and written to such as activity, tape, and task logs.

You can always use the System Internals utilities to find out exactly what is happening.

then there is always the normal type stuff such as plenty of free space on the volume and fragmentation.

 

[alpha9er]

I discovered that the same thing happens in Backup Exec on W2k8, and BuE gave me a little more detail about what is taking place during the delay: in the 'Job Status' column, it says 'Snapshot Processing'. Unfortunately, this didn't help me find a solution. I divided the disk into two partitions, one at ~20GB filled to the brim with the test data I backup* and the other for everything else. This reduced the delay to just a few seconds on both BuE and ARC. But if I include anything from the other partition (25 of 100GB used, but mostly consisting of small files) it goes to crap again.

Thanks for the reply anyway. Maybe one of these days I'll use Sysinternals to get a better look at what's going on.

*FWIW, I backup either 5, 10, or 20GB, though most of it is in a few large (1-2GB) files.

 

[davidmichel]

Perhaps this will help.

http://support.microsoft.com/kb/982018