The v10 upgrade should almost be safe now. What remains to be done is
notice when the v10 upgrade has occurred, while holding the shared lock,
and switch to using v10 lock files.
Sponsored-by: Dartmouth College's Datalad project
Upgrade the shared lock to an exclusive lock, and then delete the
lock file. If there is another process still holding the shared lock,
the first process will fail taking the exclusive lock, and not delete
the lock file; then the other process will later delete it.
Note that, in the time period where the exclusive lock is held, other
attempts to lock the content in place would fail. This is unlikely to be
a problem since it's a short period.
Other attempts to lock the content for removal would also fail in that
time period, but that's no different than a removal failing because
content is locked to prevent removal.
Sponsored-by: Dartmouth College's Datalad project
When dropping content, this was already done after deleting the content
file, but the lock file prevents deleting the directories. So, try the
deletion again.
This does mean there's a small added overhead of a failed rmdir().
Sponsored-by: Dartmouth College's Datalad project
This seems to be the best that can be done to avoid forever accumulating
the new content lock files, while being fully safe.
This is fixing code paths that have lingered unused since direct mode!
And direct mode seems to have been buggy in this area, since the content
lock file was deleted on unlock. But with a shared lock, there could be
another process that also had the lock file locked, and deleting it
invalidates that lock.
So, the lock file cannot be deleted after a shared lock. At least, not
wihout taking an exclusive lock first.. which I have not pursued yet but may.
After an exclusive lock, the lock file can be deleted. But there is
still a potential race, where the exclusive lock is held, and another
process gets the file open, just as the exclusive lock is dropped and
the lock file is deleted. That other process would be left with a file
handle it can take a shared lock of, but with no effect since the file
is deleted. Annex.Transfer also deletes lock files, and deals with this
same problem by using checkSaneLock, which is how I've dealt with it
here.
Sponsored-by: Dartmouth College's Datalad project
Windows has always used a separate lock file, but on unix, the content
file itself was locked, and in v9 that changes to also use a separate
lock file.
This needs to be tested more. Eg, what happens after dropping a file;
does the the content lock file get deleted too, or linger around?
Sponsored-by: Dartmouth College's Datalad project
Recover from corrupted content being received from a git remote due eg to a
wire error, by deleting the temporary file when it fails to verify. This
prevents a retry from failing again.
Reversion introduced in version 8.20210903, when incremental verification
was added.
Only the git remote seems to be affected, although it is certianly
possible that other remotes could later have the same issue. This only
affects things passed to getViaTmp that return (False, UnVerified) due to
verification failing. As far as getViaTmp can tell, that could just as well
mean that the transfer failed in a way that would resume, so it cannot
delete the temp file itself. Remote.Git and P2P.Annex use getViaTmp internally,
while other remotes do not, which is why only it seems affected.
A better fix perhaps would be to improve the types of the callback
passed to getViaTmp, so that some other value could be used to indicate
the state where the transfer succeeded but verification failed.
Sponsored-by: Boyd Stephen Smith Jr.
This opens the potential for the object file to be in place but
git-annex is interrupted before it can freeze it. git-annex fsck already
fixes that situation, which can also occur when lockContentForRemoval
thaws content.
Also improve comment to not be Windows-specific.
This change better supports Windows ACL management using
annex.freezecontent-command and annex.thawcontent-command and matches
the behaviour of adding an unlocked file.
By calling freezeContent after the file has moved into the annex,
the file's delete permission can be denied. If the file's delete
permission is denied before moving into the annex, the file cannot
be moved or deleted. If the file's delete permission is not denied after
moving into the annex, it will likely inherit a grant for the delete
permission which allows it to be deleted irrespective of the permissions
of the parent directory.
* When downloading urls fail, explain which urls failed for which
reasons.
* web: Avoid displaying a warning when downloading one url failed
but another url later succeeded.
Some other uses of downloadUrl use urls that are effectively internal use,
and should not all be displayed to the user on failure. Eg, Remote.Git
tries different urls where content could be located depending on how the
remote repo is set up. Exposing those urls to the user would lead to wild
goose chases. So had to parameterize it to control whether it displays urls
or not.
A side effect of this change is that when there are some youtube urls
and some regular urls, it will try regular urls first, even if the
youtube urls are listed first. This seems like an improvement if
anything, but in any case there's no defined order of urls that it's
supposed to use.
Sponsored-by: Dartmouth College's Datalad project
Except when configuration makes curl be used. It did not seem worth
trying to tail the file when curl is downloading.
But when an interrupted download is resumed, it does not read the whole
existing file to hash it. Same reason discussed in
commit 7eb3742e4b76d1d7a487c2c53bf25cda4ee5df43; that could take a long
time with no progress being displayed. And also there's an open http
request, which needs to be consumed; taking a long time to hash the file
might cause it to time out.
Also in passing implemented it for git and external special remotes when
downloading from the web. Several others like S3 are within striking
distance now as well.
Sponsored-by: Dartmouth College's DANDI project
This fixes the recent reversion that annex.verify is not honored,
because retrieveChunks was passed RemoteVerify baser, but baser
did not have export/import set up.
Sponsored-by: Dartmouth College's DANDI project
14683da9eb caused a test suite failure.
When the content of a key is not present, a LinkAnnexFailed is returned,
but replaceFile then tried to move the file into place, and since it was
not written, that crashed.
Sponsored-by: Boyd Stephen Smith Jr. on Patreon
This avoids it calling enteringStage VerifyStage when it's used in
places that only fall back to verification rarely, and which might be
called while in TransferStage and be going to perform a transfer after
the verification.
The goal is that Database.Keys be able to use it; it can't use
Annex.Content.Presence due to an import loop.
Several other things also needed to be moved to Annex.Verify as a
conseqence.
Some uses of linkFromAnnex are inside replaceWorkTreeFile, which was
already safe, but others use it directly on the work tree file, which
was race-prone. Eg, if the work tree file was first removed, then
linkFromAnnex called to populate it, the user could have re-written it in
the interim.
This came to light during an audit of all calls of addInodeCaches,
looking for such races. All the other uses of it seem ok.
Sponsored-by: Brett Eisenberg on Patreon
In Annex.Content, the object file was statted after pointer files were
populated. But if annex.thin is set, once the pointer files are
populated, the object file can potentially be modified via the hard
link. So, it was possible, though seemingly very unlikely, for the inode
of the modified object file to be cached.
Command.Fix and Command.Fsck had similar problems, statting the work
tree files after they were in place. Changed them to stat the temp file
that gets moved into place. This does rely on .git/annex being on the
same filesystem. If it's not, the cached inode will not be the same as
the one that the temp file gets moved to. Result will be that git-annex
will later need to do an expensive verification of the content of the
worktree files. Note that the cross-filesystem move of the temp file
already is a larger amount of extra work, so this seems acceptable.
Sponsored-by: Luke Shumaker on Patreon
Fix bug that caused some transfers to incorrectly fail with "content
changed while it was being sent", when the content was not changed.
While I don't know how to reproduce the problem that several people
reported, it is presumably due to the inode cache somehow being stale.
So check isUnmodified', and if it's not modified, include the file's
current inode cache in the set to accept, when checking for modification
after the transfer.
That seems like the right thing to do for another reason: The failure
says the file changed while it was being sent, but if the object file was
changed before the transfer started, that's wrong. So it needs to check
before allowing the transfer at all if the file is modified.
(Other calls to sameInodeCache or elemInodeCaches, when operating on inode
caches from the database, could also be problimatic if the inode cache is
somehow getting stale. This does not address such problems.)
Sponsored-by: Dartmouth College's Datalad project
Transfers from or to a local git repo could fail without a reason being
given, if the content failed to verify, or if the object file's stat
changed while it was being copied. Now display messages in these cases.
Sponsored-by: Jack Hill on Patreon
moveAnnex only gets to that check if the object file was not present
before. So in the case where dup files are being added repeatedly,
it will only run the first time, and so there's no significant speedup
from doing it; all it avoids is a single sqlite lookup. Since MVar
accesses do have overhead, it's better to optimise for the common case,
where unlocked files are supported.
removeAnnex is less clear cut, but I think mostly is skipped running on
keys when the object has already been dropped, so similar reasoning
applies.
This will mostly just avoid a DB lookup, so things get marginally
faster. But in cases where there are many files using the same key, it
can be a more significant speedup.
Added overhead is one MVar lookup per call, which should be small
enough, since this happens after transferring or ingesting a file,
which is always a lot more work than that. It would be nice, though,
to move getGitConfig to AnnexRead, which there is an open todo about.
All callers adjusted to update it themselves.
In Command.ReKey, and Command.SetKey, the cleanup action already did,
so it was updating the log twice before.
This fixes a bug when annex.stalldetection is set, as now
Command.Transferrer can skip updating the location log, and let it be
updated by the calling process.
Added annex.adjustedbranchrefresh git config to update adjusted branches
set up by git-annex adjust --unlock-present/--hide-missing.
Note, in a few cases, I was not able to make the adjusted branch
be updated in calls to moveAnnex, because information about what
file corresponds to a key is not available. They are:
* If two files point to one file, then eg, `git annex get foo` will
update the branch to unlock foo, but will not unlock bar, because it
does not know about it. Might be fixable by making `git annex get
bar` do something besides skipping bar?
* git-annex-shell recvkey likewise (so sends over ssh from old versions
of git-annex)
* git-annex setkey
* git-annex transferkey if the user does not use --file
* git-annex multicast sends keys with no associated file info
Doing a single full refresh at the end, after any incremental refresh,
will deal with those edge cases.
This will let a module that Annex.Content imports use inAnnex.
Unsure yet if I will need that, but this split still seems to make
sense, and Annex.Content was way too long so splitting it is good.
Lots of nice wins from this in avoiding unncessary work, and I think
nothing got slower.
This commit was sponsored by Boyd Stephen Smith Jr. on Patreon.
nukeFile replaced with removeWhenExistsWith removeLink, which allows
using RawFilePath. Utility.Directory cannot use RawFilePath since setup
does not depend on posix.
This commit was sponsored by Graham Spencer on Patreon.
This was already prevented in other ways, but as seen in commit
c30fd24d91, those were a bit fragile.
And I'm not sure races were avoided in every case before. At least a
race between two separate git-annex processes, dropping the same
content, seemed possible.
This way, if locking fails, and the content is not present, it will
always do the right thing. Also, it avoids the overhead of an unncessary
inAnnex check for every file.
This commit was sponsored by Denis Dzyubenko on Patreon.
This is groundwork for external backends, but also makes sense to keep
this information with the rest of a Backend's implementation.
Also, removed isVerifiable. I noticed that the same information is
encoded by whether a Backend implements verifyKeyContent or not.
Only supported by some special remotes: directory
I need to check the rest and they're currently missing methods until I do.
git-annex sync --no-content does not yet use this to do imports
When storing content on remote fails, always display a reason why.
Since the Storer used by special remotes already did, this mostly affects
git remotes, but not entirely. For example, if git-lfs failed to connect to
the endpoint, it used to silently return False.
This does mean that RemoteDaemon.Transport.Tor's call runs it, otherwise
no change, but this is groundwork for doing more such expensive actions
in dupState.
using git credential to get the password
One thing this doesn't do is wrap the password prompting inside the prompt
action. So with -J, the output can be a bit garbled.
Remove dup definitions and just use the RawFilePath one. </> etc are
enough faster that it's probably faster than building a String directly,
although I have not benchmarked.
git-annex find is now RawFilePath end to end, no string conversions.
So is git-annex get when it does not need to get anything.
So this is a major milestone on optimisation.
Benchmarks indicate around 30% speedup in both commands.
Probably many other performance improvements. All or nearly all places
where a file is statted use RawFilePath now.
Adds a dependency on filepath-bytestring, an as yet unreleased fork of
filepath that operates on RawFilePath.
Git.Repo also changed to use RawFilePath for the path to the repo.
This does eliminate some RawFilePath -> FilePath -> RawFilePath
conversions. And filepath-bytestring's </> is probably faster.
But I don't expect a major performance improvement from this.
This is mostly groundwork for making Annex.Location use RawFilePath,
which will allow for a conversion-free pipleline.
Finally builds (oh the agoncy of making it build), but still very
unmergable, only Command.Find is included and lots of stuff is badly
hacked to make it compile.
Benchmarking vs master, this git-annex find is significantly faster!
Specifically:
num files old new speedup
48500 4.77 3.73 28%
12500 1.36 1.02 66%
20 0.075 0.074 0% (so startup time is unchanged)
That's without really finishing the optimization. Things still to do:
* Eliminate all the fromRawFilePath, toRawFilePath, encodeBS,
decodeBS conversions.
* Use versions of IO actions like getFileStatus that take a RawFilePath.
* Eliminate some Data.ByteString.Lazy.toStrict, which is a slow copy.
* Use ByteString for parsing git config to speed up startup.
It's likely several of those will speed up git-annex find further.
And other commands will certianly benefit even more.
This will speed up the common case where a Key is deserialized from
disk, but is then serialized to build eg, the path to the annex object.
Previously attempted in 4536c93bb2
and reverted in 96aba8eff7.
The problems mentioned in the latter commit are addressed now:
Read/Show of KeyData is backwards-compatible with Read/Show of Key from before
this change, so Types.Distribution will keep working.
The Eq instance is fixed.
Also, Key has smart constructors, avoiding needing to remember to update
the cached serialization.
Used git-annex benchmark:
find is 7% faster
whereis is 3% faster
get when all files are already present is 5% faster
Generally, the benchmarks are running 0.1 seconds faster per 2000 files,
on a ram disk in my laptop.
