[[!comment format=mdwn
 username="joey"
 subject="""comment 5"""
 date="2016-02-05T17:01:24Z"
 content="""
@luca you might get that with -J2 if you have two work tree files that
point to the same key. The first thread will start copying the first file,
and then the second thread tries to copy the second file but sees the key
is already being copied.

It shouldn't happen otherwise; the way -J works is it splits files between
threads. So, no two threads will be working on the same file, except in the
situation described above.

I doubt that whatever you're seeing is the same problem originally
described in this bug report. I'm still waiting for a followup with missing
information about the originally described bug.
"""]]