All changes to files in the branch are now made via pure functions that
transform the old file into the new. This will allow adding locking
to prevent read/write races. It also makes the code nicer, and purer.
I noticed a behavior change, really a sort of bug fix. Before,
'git annex untrust foo --trust bar' would change both trust levels
permanantly, now the --trust doesn't get stored.
Actually, let's do a targeted fix of the actual forkProcess that was not
waited on. The global reap is moved back to the end, after the long-running
git processes actually exit.
This yields a second or so speedup in unused, find, etc. Seems that even
when the ByteString is immediately split and then converted to Strings,
it's faster.
I may try to push ByteStrings out into more of git-annex gradually,
although I suspect most of the time-critical parts are already covered
now, and many of the rest rely on libraries that only support Strings.
Added Git.ByteString which replaces Git IO methods with ones using lazy
ByteStrings. This can be more efficient when large quantities of data are
being read from git.
In Git.LsTree, parse git ls-tree output more efficiently, thanks
to ByteString. This benchmarks 25% faster, in a benchmark that includes
(probably predominately) the run time for git ls-tree itself.
In real world numbers, this makes git annex unused 2 seconds faster for
each branch it needs to check, in my usual large repo.
Fixed the laziness space leak, so it runs in 60 mb or so again. Slightly
faster due to using Data.Set.difference now, although this also makes it
use slightly more memory.
Also added display of the refs being checked, and made unused --from
also check all refs for things in the remote.
