I recently migrated some of my repositories from WORM to SHA1E, and
noticed after finishing conversion and dropping all WORM keys that
there are some stale files and directories left over in the
.git/annex/objects directory. These seem to fall into two categories:

1. There are some empty directories meant for WORM-keys. Strangely, I
don’t believe the content of these keys has ever been present on this
machine, and the corresponding .log files do not contain the local
UUID. What might be the deal with those?

Another set of empty WORM directories housed content I unannexed and
checked into regular git on my other remote, and then pulled locally.
A subsequent «dropunused» seems to have left the empty directories
after dropping their content.

I suppose the stale directories can be safely pruned away?

One thing I noticed is that, while the terminal leaf in the objects
directory is usually sticky (mode +t), the stale directories to
content I unannexed are all non-sticky. Maybe this gives some
indication where things got stuck? A few (though not all) of the other
terminal directories are non-sticky, as well.

2. There are some .map and .cache files leftover in
.git/annex/objects. This is an indirect repository, but I briefly
switched it to direct once. The stale files seem to belong to content
with which I had some difficulties when «git annex add»’ing the files
(I recall I had to add them multiple times before they were correctly
indexed). I now examined these files again and noticed they were
tracked via regular git. I «git rm»’ed them and readded them into the
annex. Can the stale .cache and .map files be safely deleted?

I noticed some of these keys have the format
«WORM-s123-m-123456789--name», with an additional dash before the
mtime. Has there been a format change, or does this indicate a
problem?

Best regards,
Z.
