This avoids starting one process when only the other one is needed.
Eg in git-annex smudge --clean, this reduces the total number of
cat-file processes that are started from 4 to 2.
The only performance penalty is that when both are needed, it has to do
twice as much work to maintain the two Maps. But both are very small,
consisting of 1 or 2 items, so that work is negligible.
Sponsored-by: Dartmouth College's Datalad project
This is only needed for the i386ancient build, so build in the git
version git-annex is built with, assuming git won't be upgraded, or if
it is, they just won't get the speedup of --buffer
This was a bit disappointing, I was hoping for a 2x speedup. But, I think
the metadata lookup is wasting a lot of time and also needs to be made to
stream.
The changes to catObjectStreamLsTree were benchmarked to not also speed
up --all around 3% more. Seems I managed to make it polymorphic after all.
The catObjectStream' is generic enough to let it be nicely used from
inside Annex monad.
Chan will be faster than DList here. Bearing in mind, it is unbounded,
but in reality will be bounded by the size of the stdio buffer through
git cat-file.
This speeds up --all by about 10% although I think only getting back to
the previous performance before I introduced that DList.
Turns out the %(rest) trick was not needed. Instead, just maintain a
list of files we've asked for, and each cat-file response is for the
next file in the list.
This actually benchmarks 25% faster than before! Very surprising, but it
must be due to needing to shove less data through the pipe, and parse
less.
This assumes that no location log files will have a newline or carriage
return in their name. catObjectStream skips any such files due to
cat-file not supporting them.
Keys have been prevented from containing newlines since 2011,
commit 480495beb4. If some old repo
had a key with a newline in it, --all will just skip processing that key.
Other things, like .git/annex/unused files certianly assume no newlines in
keys too, and AFAICR, such keys never actually worked.
Carriage return is escaped by preSanitizeKeyName since 2013. WORM keys
generated before that point could perhaps contain a CR. (URL probably not,
http probably doesn't support an URL with a raw CR in it.) So, added
a warning in fsck about such keys. Although, fsck --all will naturally
skip them, so won't be able to warn about them. Not entirely
satisfactory, but I'll bet there are not really any such keys in
existence.
Thanks to Lukey for finding this optimisation.
This handles all sites where checkSuccessProcess/ignoreFailureProcess
is used, except for one: Git.Command.pipeReadLazy
That one will be significantly more work to convert to bracketing.
(Also skipped Command.Assistant.autoStart, but it does not need to
shut down the processes it started on exception because they are
git-annex assistant daemons..)
forceSuccessProcess is done, except for createProcessSuccess.
All call sites of createProcessSuccess will need to be converted
to bracketing.
(process pools still todo also)
Around 3% total speedup.
Profiling git annex find --not --in web, it's now bytestring end-to-end,
and there is only a little added overhead in eg accessing the Annex
state MVar (3%). The rest of the runtime is spent reading symlinks, and
in attoparsec.
This feels like the end of the optimisation road, without a major change
like caching information for faster queries.
Git will eventually switch to sha2 and there will not be one single
shaSize anymore, but two (40 and 64).
Changed all parsers for git plumbing output to support both sizes of
shas.
One potential problem this does not deal with is, if somewhere in
git-annex it reads two shas from different sources, and compares them
to see if they're the same sha, it would fail if they're sha1 and sha256
of the same value. I don't know if that will really be a concern.
smudge: When annex.largefiles=anything, files that were already stored in
git, and have not been modified could sometimes be converted to being
stored in the annex. Changes in 7.20191024 made this more of a problem.
This case is now detected and prevented.
Goal is to make git-annex faster by using ByteString for all the
worktree traversal. For now, this is focusing on Command.Find,
in order to benchmark how much it helps. (All other commands are
temporarily disabled)
Currently in a very bad unbuildable in-between state.
Work around git cat-file --batch's odd stripping of carriage return from
the end of the line (some windows infection), avoiding crashing when the
repo contains a filename ending in a carriage return.
This typo would make "git cat-file cat-file" fail, and the way it's used,
I think it broke querying all info from filenames containing newlines,
because the other queries are only run when it succeeds.
This does not change the overall license of the git-annex program, which
was already AGPL due to a number of sources files being AGPL already.
Legally speaking, I'm adding a new license under which these files are
now available; I already released their current contents under the GPL
license. Now they're dual licensed GPL and AGPL. However, I intend
for all my future changes to these files to only be released under the
AGPL license, and I won't be tracking the dual licensing status, so I'm
simply changing the license statement to say it's AGPL.
(In some cases, others wrote parts of the code of a file and released it
under the GPL; but in all cases I have contributed a significant portion
of the code in each file and it's that code that is getting the AGPL
license; the GPL license of other contributors allows combining with
AGPL code.)
Work around git cat-file --batch's protocol not supporting newlines by
running git cat-file not batched and passing the filename as a
parameter.
Of course this is quite a lot less efficient, especially because it
currently runs it multiple times to query for different pieces of
information.
Also, it has subtly different behavior when the batch process was
started and then some changes were made, in which case the batch process
sees the old index but this workaround sees the current index. Since
that batch behavior is mostly a problem that affects the assistant and has
to be worked around in it, I think I can get away with this difference.
I don't know of any other problems with newlines in filenames, everything
else in git I can think of supports -z. And git-annex's json output
supports newlines in filenames so downstream parsers from git-annex will be ok.
git-annex commands that use --batch themselves don't support newlines
in input filenames; using --json --batch is currently a way around that
problem.
This commit was sponsored by Ewen McNeill on Patreon.
Removed dependency on MissingH, instead depending on the split
library.
After laying groundwork for this since 2015, it
was mostly straightforward. Added Utility.Tuple and
Utility.Split. Eyeballed System.Path.WildMatch while implementing
the same thing.
Since MissingH's progress meter display was being used, I re-implemented
my own. Bonus: Now progress is displayed for transfers of files of
unknown size.
This commit was sponsored by Shane-o on Patreon.
Restarting a crashing git process could result in filename encoding issues
when not in a unicode locale, as the restarted processes's handles were not
read in raw mode.
Since rawMode is always used when starting a coprocess, didn't bother
to parameterise it and just always enable it for simplicity.
This commit was sponsored by Jake Vosloo on Patreon.
.. and have to be checked to see if they are a pointed to an annexed file.
Cases where such memory use could occur included, but were not limited to:
- git commit -a of a large unlocked file (in v5 mode)
- git-annex adjust when a large file was checked into git directly
Generally, any use of catKey was a potential problem.
Fix by using git cat-file --batch-check to check size before catting.
This adds another git batch process, which is included in the CatFileHandle
for simplicity.
There could be performance impact, anywhere catKey is used. Particularly
likely to affect adjusted branch generation speed, and operations on
unlocked files in v6 mode. Hopefully since the --batch-check and
--batch read the same data, disk buffering will avoid most overhead.
Leaving only the overhead of talking to the process over the pipe and
whatever computation --batch-check needs to do.
This commit was sponsored by Bruno BEAUFILS on Patreon.
This fixes all instances of " \t" in the code base. Most common case
seems to be after a "where" line; probably vim copied the two space layout
of that line.
Done as a background task while listening to episode 2 of the Type Theory
podcast.
Removed instance, got it all to build using fromRef. (With a few things
that really need to show something using a ref for debugging stubbed out.)
Then added back Read instance, and made Logs.View use it for serialization.
This changes the view log format.
This is a massive win on OSX, which doesn't have a sha256sum normally.
Only use external hash commands when the file is > 1 mb,
since cryptohash is quite close to them in speed.
SHA is still used to calculate HMACs. I don't quite understand
cryptohash's API for those.
Used the following benchmark to arrive at the 1 mb number.
1 mb file:
benchmarking sha256/internal
mean: 13.86696 ms, lb 13.83010 ms, ub 13.93453 ms, ci 0.950
std dev: 249.3235 us, lb 162.0448 us, ub 458.1744 us, ci 0.950
found 5 outliers among 100 samples (5.0%)
4 (4.0%) high mild
1 (1.0%) high severe
variance introduced by outliers: 10.415%
variance is moderately inflated by outliers
benchmarking sha256/external
mean: 14.20670 ms, lb 14.17237 ms, ub 14.27004 ms, ci 0.950
std dev: 230.5448 us, lb 150.7310 us, ub 427.6068 us, ci 0.950
found 3 outliers among 100 samples (3.0%)
2 (2.0%) high mild
1 (1.0%) high severe
2 mb file:
benchmarking sha256/internal
mean: 26.44270 ms, lb 26.23701 ms, ub 26.63414 ms, ci 0.950
std dev: 1.012303 ms, lb 925.8921 us, ub 1.122267 ms, ci 0.950
variance introduced by outliers: 35.540%
variance is moderately inflated by outliers
benchmarking sha256/external
mean: 26.84521 ms, lb 26.77644 ms, ub 26.91433 ms, ci 0.950
std dev: 347.7867 us, lb 210.6283 us, ub 571.3351 us, ci 0.950
found 6 outliers among 100 samples (6.0%)
import Crypto.Hash
import Data.ByteString.Lazy as L
import Criterion.Main
import Common
testfile :: FilePath
testfile = "/run/shm/data" -- on ram disk
main = defaultMain
[ bgroup "sha256"
[ bench "internal" $ whnfIO internal
, bench "external" $ whnfIO external
]
]
sha256 :: L.ByteString -> Digest SHA256
sha256 = hashlazy
internal :: IO String
internal = show . sha256 <$> L.readFile testfile
external :: IO String
external = do
s <- readProcess "sha256sum" [testfile]
return $ fst $ separate (== ' ') s
Done using a mode witness, which ensures it's fixed everywhere.
Fixing catFileKey was a bear, because git cat-file does not provide a
nice way to query for the mode of a file and there is no other efficient
way to do it. Oh, for libgit2..
Note that I am looking at tree objects from HEAD, rather than the index.
Because I cat-file cannot show a tree object for the index.
So this fix is technically incomplete. The only cases where it matters
are:
1. A new large file has been directly staged in git, but not committed.
2. A file that was committed to HEAD as a symlink has been staged
directly in the index.
This could be fixed a lot better using libgit2.
This runs git-cat-file in non-batch mode for all files with spaces.
If a directory tree has a lot of them, and is in direct mode, even "git
annex add" when there are few new files will need a *lot* of forks!
The only reason buffering the whole file content to get the sha is not a
memory leak is that git-annex only ever uses this on symlinks.
This needs to be reverted as soon as a fix is available in git!
Fuzz tests have shown that git cat-file --batch sometimes stops running.
It's not yet known why (no error message; repo seems ok). But this is
something we can deal with in the CoProcess framework, since all 3 types of
long-running git processes should be restartable if they fail.
Note that, as implemented, only IO errors are caught. So an error thrown
by the reveiver, when it sees something that is not valid output from
git cat-file (etc) will not cause a restart. I don't want it to retry
if git commands change their output or are just outputting garbage.
This does mean that if the command did a partial output and crashed in the
middle, it would still not be restarted.
There is currently no guard against restarting a command repeatedly, if,
for example, it crashes repeatedly on startup.
