Get rid of cleanFolder() in the Watcher if possible for performance

[PVince81]

After debugging the watcher/scanner, I noticed that at the end of the scan session it will call cleanFolder($path) and will iterate over all cache entries inside that folder and call file_exists to find out whether the file still exists.

As far as I understand, diffing the children of a folder is already done in scanChildren, so not sure why it has to be done again here.

@icewind1991 can you clarify ? Can we get rid of this extra cleanup to gain some performance ?

[PVince81]

https://github.com/owncloud/core/blob/v9.0.1/lib/private/files/cache/watcher.php#L132

[PVince81]

Found this: https://github.com/owncloud/core/blob/v9.0.1/lib/private/files/cache/scanner.php#L397

Maybe we didn't have this piece about $removedChildren in the past which would explain the requirement for cleanFolder

[PVince81]

Fixed through #25103

[PVince81]

Hmm, that PR is only for fed shares.

I think we should eventually get rid of it completely.