Some of the things git-annex transferkeys does are suboptimal, especially when -J has many of them running.

In particular, it writes location logs when downloading (but not uploading), and so it flushes the journal etc.

done --Joey

It may also do some queries of data from git that could be avoided with some refactoring of what code runs in it, which could avoid it needing to start up git helper processes like catkey. --Joey

Still starts some git catkey processes, but I guess it's for good reason. --Joey