Determine deduplication ratio

robnicholson · Wed Apr 03, 2013 8:07 am

How do you determine how much data is getting deduplicated, i.e. the deduplication ratio of the spdata file?

We're evaluating DPM 2012 in the lab and this product is renowned for requiring large amounts of disk space. Microsoft recommends 3rd party tools to add deduplication to the DPM store so we thought "hey, we've got StarWind - let's give that a whirl".

So we've backed up a file share to DPM and now I'd like to monitor the deduplication ratio on the StarWind disk itself.

Cheers, Rob.

Wed Apr 03, 2013 8:39 am

Hi Rob,
There's no direct dd ratio information in the console for now, so the ratio should be calculated.
Note the size of the folder which contains the deduplication device files, then do a test backup to this folder, now compare the folder size with the backup job size.
Please note: current version of the deduplication engine is not shrinking when deleting unassociated blocks, so even if you delete the old backup - the dd device folder size will remain the same.

robnicholson · Wed Apr 03, 2013 8:57 am

Hi Max,

That's a bit of an omission as with DPM it's very difficult to determine exact disk usage. Can I ask why there is no way to report on this vital statistic?

Cheers, Rob.

Wed Apr 03, 2013 2:03 pm

We're working on this statistic, since deduplication will be reworked with our new FS in mind it will be pretty easy to do.
Current version is a small development of what we've built to work with Veeam according to Global deduplication plan.
New version is something we're planning to push into production environment.

robnicholson · Wed May 01, 2013 3:18 pm

Hi Max,

Still looking forward with bated breath to the new version. Display of dedupe ratio is a basic requirement. We're trialled Windows Server 2012 dedupe on a copy of our file server and it got a massive 45% ratio. Impressive.

Cheers, Rob.

Tue May 14, 2013 4:21 pm

Hi Rob,
I'm eager to help you, but I still haven't got a beta I can give to our clients.
As soon as I get it - me or Anton will make a big announcement on the forum.
I understand that it's been a long time, but please be sure that it is worth waiting for.