Difference in backup file sizes between V5 and v6

[gchapman]

I'm testing out Version 6 for deployment right now. We have been running version 5 for the last year and a half with no issues. I really like the concepts behind the proxy use and it is weighing heavily in my design choices for the future.

That said, I've found something that is substantially different between version 5 and version 6, and that is the size of the backup files on the disk. I've run a few tests and it appears that version 6 is using about 75% more disk space than version 5 did.

Case in point, a backup job of 3 sql servers with a total space of 615GB results in a backup file of roughly 105GB on the backup target disk in version 5. In version 6, the same servers being backup up show a backup file size of 471GB.

Version 5 report shows: 602Gb Data Size - Backup Size 102GB - DeDupe 78% - Compression 21%
Version 6 report shows: 602Gb Data Size - Backup Size 471GB - DeDupe 78% - Compression 100%

Both jobs are configured the same:
Reverse Incremental
Enable In line Dedeupe at Optimal Compression and Optimized for local target.
Change Block is active

So any idea why the difference in the backup file size?

[tsightler]

It's obvious from the stats that, for some reason, you are not getting any compression with the V6 setup. I have never seen this happen if compression was actually set on the job. What are you using for a repository? Do you perhaps have the repository configured to uncompress the data prior to writing to disk? If there's no obvious setting difference then you should have support investigate the logs for an explanation.

[gchapman]

It's obvious from the stats that, for some reason, you are not getting any compression with the V6 setup. I have never seen this happen if compression was actually set on the job. What are you using for a repository? Do you perhaps have the repository configured to uncompress the data prior to writing to disk? If there's no obvious setting difference then you should have support investigate the logs for an explanation.

Bingo! I didn't see that on the repository it was set to decompress. #facepalm I don't recall having the options to set repository configurations on v5. Thanks.

[tsightler]

Yep, this is a new feature that is designed primarily for writing to dedupe appliance. You can still leverage compression between the proxies and repositories, which is useful to reduce the amount of traffic, especially for off-site backup, and then uncompress the data on the repository prior to writing it to the dedupe appliance so you still get the full effect of your hardware deduplication. Glad it was that simple.