Defragmenting Backups

[5150cd]

I'm running VBR on a dedicated physical server. I'm curious if anybody has any thoughts on defragmenting the server. I've noticed that the backups do get quite fragmented, and I have a custom MyDefrag script to keep things cleaned up, but I'm wondering if it's worth the time involved to move all the backups around. In other words, does Veeam take a substantial performance hit by having the files fragmented?

I'm running reverse incrementals on all my backups if it makes any difference. Thanks!

edit: Also, in case any one is interested, my MyDefrag script moves all the vbk's to the front of the disk with a small gap between each one and then all the vrb files crammed to the end of the disk. I'm always messing with it, but if you want a copy let me know.

[foggy]

Chris, I would assume that you will not get any significant benefit from defragmenting the backup drive since the backup files are compressed and deduped and still require a considerable time to deal with them (besides the time required to read the whole file). Moreover, possibly it is not a very good idea as there's always a risk of getting corrupt backups as a result of defragmentation gestures making it impossible to restore. Thanks.

[Gostev]

Even if the backup files are defragmented, the access pattern to data inside is still fairly random (Veeam backup file is essentially deduped block storage). I agree, it makes little sense to defragment them.

[J1mbo]

It's not something I do, rather make sure the array is working as well as it can (so avoid RAID5/6 at all costs), use (and enabled) BBWC, have plenty of RAM in the host (file system cache) and if using SATA drives ensure the controller supports SATA NCQ. I've been using WD's RE4 drives, which have enhanced short-seek speed, but the machine does take a long time to transform the synthetic fulls even so.

Creating files at 'each end' of the drive may be counter productive if the application then has to generate a wealth of agonisingly slow full-stroke IO.

[5150cd]

Thanks for the info guys, I appreciate it! I do regret doing the array in RAID 5, but when I ran my backups this morning all of them were done in 13 minutes so I don't think it's worth burning the system down to do a RAID 10 at this point.