Verifying backend time increases tenfold after specifying retention



For the last year or so I have been letting Duplicati just keep all version of backups and my backups took 2-3 hours each time. Last month I specified retention policy as “1W:1D,1M:1W,5Y:1M” and now every time it backs up it takes 2-3 days “Verifying Backend Data”.

Is this something I just have to accept if I want Duplicate to manage versions or is it an issue that can be resolved.

I have reviewed the myriad articles on the forum related to “Verifying Backend Data” and none seem to address my particular situation.


I don’t believe I noticed any difference when I started using a retention policy. If you remove the policy and just go back to “keep all versions” does the problem go away?

If so maybe set the retention policy again and then check the live log to see what it’s doing that takes so long: About / Show Log / Live and set it to Verbose.


Did you try the “analyze” command against your SQL databases to see if that made a difference? I was one of those that suffered from extremely long verifications (I’m using “1W:1D,1M:1W,3Y:1M” as my retention) and this resolved it within a few minutes.


What do you mean by “analyze”? I only see Repair, Delete, and Recreate

Maybe I am not looking in the right place?


I have not tried removing the retention policy yet.

I have spent a lot of time monitoring the live log and it is doing downloads and verifications, albeit at an apparently slow place. A single core of the CPU is at 100% the entire time.


Unfortunately at the moment “analyze” is not part of Duplicati, you have to install something like “DB Browser for SQLite”. Close down Duplicati, then open the database you see in your screen shot, an in the SQL tab execute “analyze” as a command and wait. Then save the database and close, restart Duplicati and let it get on. Would be wise to back up the database beforehand of course.