Cleanup/maintenance after initial ingestion to B2

[1wanderingexpat]

I have now completed a full backup ingestion of one bucket in my B2 account. As I’ve been backing up this data, I’ve been running these commands once daily:

check -fossils
prune -keep 0:180 -keep 7:30 -keep 1:7 -a

Questions:

1. Now that I’ve completed a full backup, should I run a more thorough prune such as
   prune -exhaustive once to clean up unreferenced chunks? If so, do I run that as a separate prune command (without the -keep options) on its own?
2. Other than the -keep prune I’ve been running, are there other maintenance actions I should be running on this backup?
3. Is there any point in running a prune with -keep options as I have been above during ingestion or should just run prune alone with no options during the initial ingestion of a backup storage?
4. Finally, specific to B2, I’m assuming that I can run parallel prune commands on backups that are in different B2 buckets. Is that correct?

It would be useful if this were all spelled out somewhere easily accessible. Maybe I’m not looking hard enough, but I’m not seeing many actual explanations in the “Guides”, mostly a list of commands and their basic purpose and optional switches. Clearly written by someone who completely understands the entire concept of Duplicacy, but doesn’t realize that not everyone else does.

[saspus]

There is no maintenance of any kind required. Running prune right after initial backup is pointless, and during initial backup is pretty much noop

The only point in prune is to save space on storage by reducing backup frequency if you have a lot of volatile transient data. If not — I.e. if you backup usual home users stuff, like documents photos and videos — prune accomplishes very little.

I would not prune at all; in this case you can harden your solution further by forbidding delete and modify access to the storage.

I used to prune, but no longer do: there is long standing bug that if prune is interrupted for any reason the ghost snapshot that was going to be deleted will remain on storage, causing next check to fail. The bug was reported multiple times, solution was suggested but I don’t think it’s fixed yet. Therefore not pruning results in less headaches.

"Missing Chunks" reported following a purge

Likely what happened here is one of prunes did not compete or otherwise failed to delete snapshots after deleting chunks leaving ghost snapshots. Delete those snapshots manually and clear local cache. I had similar thing happen recently described here: -exhaustive implies -exclusive? Corrupted snapshots, can't delete with "No snapshot to delete" @gchen, prune shall first delete snapshot and then its chunks. If prune is interrupted or fails mid way it’s much better to leave orphan chunks in th…

[1wanderingexpat]

@saspus

if you backup usual home users stuff, like documents photos and videos — prune accomplishes very little.

Two of my bucket backups are of this nature, but one is a backup of backups. IOW, all my lan client systems backup to a shared folder using a proprietary app (or tar/gz). These files change as incremental and full backups get added/replaced daily and weekly. Might it be beneficial to run prune on this backup storage?