Wide variance in backup performace - ideas?

[NetAdMBC]

Using Endpoint Backup 1.5 to back up a physical Exchange 2010 server to a Veeam B&R 9.5 repository. I notice wide variance in time it take to finish a backup- for instance, here's the last seven days (all taken at 1:30 am), backup size and time:

Thursday - 22.4 GB 0:47:11
Friday - 21.2 GB 9:07:47 (!)
Saturday - 18.3 GB 0:43:36
Sunday - 9.39 GB 1:21:34 (NB: half the size of the previous night, takes twice as long)
Monday - 6.62 GB 0:41:28
Tuesday - 23.4 GB 0:44:16
Wednesday - 22.2 GB 9:49:57 (again, !)

Pretty consistant amounts of data (smaller on weekends, but consistent during the week), but GB/min varies like mad. Can anyone hypothesize why? I've looked at jobs on the server, but there don't appear to be any that run some days and not others, and at the backup target, which gets the same jobs thrown at it every night. Anywhere I should be looking that I'm not seeing?

[jmmarton]

You'll probably need to take a look at the logs to see what's really going on. You might also want to upgrade from VEB 1.5 to VAW 2.0.

Joe

[Dima P.]

Hi NetAdMBC,

How long is your backup chain? Any chance merge is performed at these days? Thanks.

[NetAdMBC]

Backup chain is 14 days, and there is a merge at the end of every night's backup, so I doubt that's the issue.

I did upgrade to VAW2.0, since I'd been meaning to anyway. The past week has been more consistent - no 9 hour backups - but still varies quite a bit:
Saturday - 18.2 GB 1:58:04
Sunday - 7.40 GB 1:23:07
Monday - 6.35 GB 3:18:51
Tuesday - 19.7 GB 2:13:49
Wednesday - 23.8 GB 4:18.52
Thursday - 23.1 GB 2:34.05
Friday - 20.2 GB 2:21:55

I'm not particularly worried about it now, if it keeps to the 2-3 hour range like this. I looked at the RAID controller for any messages of underlying hardware problems - like, "it tried to write to the one block for a hour and kept failing" - but didn't see anything like that. I'll keep looking through the logs for hints.

[Dima P.]

Indeed, looks better now. VAW 20 has lots of fixes included - this might be the reason why backup performance improved.