Much of the memory bloat turned out to be due to getKeysReferenced
containing a mapM, which is strict and buffered the whole list
rather than streaming it.
The other half of the bloat was due to building a temporary Set
in order to call S.difference. While that is more cpu efficient,
I switched to successive S.delete, since with it, I can run a whole
git annex unused in less than 8 mb of memory.
The whole Set of keys with content available is still stored in memory,
so running unused in a repo with a whole lot of file content will still
use more memory. In a repo containing 6000 files, it needed 40 mb.
Note that the status command still uses the bloatful getKeysReferenced.
This has two benefits.
1. When a lot of refs are going to be received, get them via lower cost
connection when possible.
2. Allows ctrl-c of sync after the cheaper remotes have been pulled from
(or pushed to).
Rather than running make, which runs configure, let Setup.hs just include
the configure code. The standalone configure is retained for use by the
Makefile.
This may work better with cabal-dev, since it avoids the Makefile running
ghc, and lets cabal handle all the compiler running, with whatever
flags it uses to expose dependencies.
Fix Key directory hash calculation code to behave as it did before version
3.20120227 when a key contains non-ascii.
The hash directories for a given Key are based on its md5sum.
Prior to ghc 7.4, Keys contained raw, undecoded bytes, so the md5sum was
taken of each byte in turn. With the ghc 7.4 filename encoding change,
keys contains decoded unicode characters (possibly with surrigates for
undecodable bytes). This changes the result of the md5sum, since the md5sum
used is pure haskell and supports unicode. And that won't do, as git-annex
will start looking in a different hash directory for the content of a key.
The surrigates are particularly bad, since that's essentially a ghc
implementation detail, so could change again at any time. Also, changing
the locale changes how the bytes are decoded, which can also change
the md5sum.
Symptoms would include things like:
* git annex fsck would complain that no copies existed of a file,
despite its symlink pointing to the content that was locally present
* git annex fix would change the symlink to use the wrong hash
directory.
Only WORM backend is likely to have been affected, since only it tends
to include much filename data (SHA1E could in theory also be affected).
I have not tried to support the hash directories used by git-annex versions
3.20120227 to 3.20120308, so things added with those versions with WORM
will require manual fixups. Sorry for the inconvenience!
This is a straight up pure-code stinker. The relative path calculation
looked for common subdirectories in the two paths, but failed to stop
after the paths diverged. When a later pair of subdirectories were the
same, the resulting relative path was wrong.
Added regression test for this.
Locking is used, so that, if there are multiple git-annex processes
using a remote concurrently, the stop hook is only run by the last
process that uses it.
That was actually really easy. But, when getting a file from an encrypted
directory special remote, no meter can be shown, because the total file
size is not known.
Avoiding writing files larger than a specified size is useful on certian
things. For example, box.com has a file size limit of 100 mb. Could also
be useful on really crappy removable media.
