On a local non-NFS filesystem the .git/config file will be orphaned if
it is replaced by a new process while the current process is reading the
old file. The current process successfully continues to read the
orphaned file until it closes the file handle.
Since NFS servers do not keep track of open files, instead of orphaning
the old .git/config file, such a replacement on an NFS filesystem will
instead cause the old file to be garbage collected (deleted). A stale
file handle exception will be raised on NFS clients if the file is
garbage collected (deleted) on the server while it is being read. Since
we no longer have access to the old file in these cases, the previous
code would just fail. However, in these cases, reopening the file and
rereading it will succeed (since it will open the new replacement file).
Since retrying the read is a viable strategy to deal with stale file
handles on the .git/config file, implement such a strategy.
Since it is possible that the .git/config file could be replaced again
while rereading it, loop on stale file handle exceptions, up to 5 extra
times, trying to read the .git/config file again, until we either read
the new file, or find that the file no longer exists. The limit of 5 is
arbitrary, and provides a safe upper bounds to prevent infinite loops
consuming resources in a potential unforeseen persistent error
condition.
Change-Id: I6901157b9dfdbd3013360ebe3eb40af147a8c626
Signed-off-by: Nasser Grainawi <nasser@codeaurora.org>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
When running on NFS there was a chance that JGits LockFile
semantic is broken because File#createNewFile() may allow
multiple clients to create the same file in parallel. This
change provides a fix which is only used when the new config
option core.supportsAtomicCreateNewFile is set to false. The
default for this option is true. This option can only be set in the
global or the system config file. The repository config file is not
taken into account in this case.
If the config option core.supportsAtomicCreateNewFile is true
then File#createNewFile() is trusted and the behaviour doesn't
change.
But if core.supportsAtomicCreateNewFile is set to false then after
successful creation of the lock file a hardlink to that lock file is
created and the attribute nlink of the lock file is checked to be 2. If
multiple clients manage to create the same lock file nlink would be
greater than 2 showing the error.
This expensive workaround is described in
https://www.time-travellers.org/shane/papers/NFS_considered_harmful.html
section III.d) "Exclusive File Creation"
Change-Id: I3d2cc48d8eb280d5f7039eb94da37804f903be6a
Honor trustFolderStats also when reading packed-refs
Then list of packed refs was cached in RefDirectory based on mtime of
the packed-refs file. This may fail on NFS when attributes are cached.
A cached mtime of the packed-refs file could cause JGit to trust the
cached content of this file and to overlook that the file is modified.
Honor the config option trustFolderStats and always read the packed-refs
content if the option is false. By default this option is set to true
and this fix is not active.
Change-Id: I2b65cfaa8f4aba2efbf8a5e865d3f09f927e2eec
Fix exception handling for opening bitmap index files
When creating a new PackFile instance it is specified whether this pack
has an associated bitmap index file or not. This information is cached
and the public method getBitmapIndex() will always assume a bitmap index
file must exist if the cached data tells so. But it may happen that the
packfiles are repacked during a gc in a different process causing the
packfile, bitmap-index and index file to be deleted. Since JGit still
has an open FileHandle on the packfile this file is not really deleted
and can still be accessed. But index and bitmap index file are deleted.
Fix getBitmapIndex() to invalidate the cached packfile instance if such
a situation occurs.
This problem showed up when a gerrit server was serving repositories
which where garbage collected with native git regularly. Fetch and
clone commands for certain repositories failed permanently after a
native git gc had deleted old bitmap index files.
Change-Id: I8e620bec74dd3f310ba42024f9a657062f868f0e
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Use a dedicated executor to run auto-gc in command line interface
WorkQueue uses daemon threads so auto-gc would not be executed after
short-lived commands run in command line. Hence use a dedicated executor
which we shutdown when the command finishes.
Change-Id: I0c2429ecfa04387389d159168ba78a020a696228
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Allow to use an external ExecutorService for background auto-gc
If set use the external executor, otherwise use JGit's own simple
WorkQueue. Move WorkQueue to an internal package so we can reuse it
without exposing it in the public API.
Change-Id: I060d62ffd6692362a88b4bf13ee07b0dc857abe9
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Fetch: Add --recurse-submodules and --no-recurse-submodules options
Add options to control recursion into submodules on fetch.
Add a callback interface on FetchCommand, to allow Fetch to display
an update "Fetching submodule XYZ" for each submodule.
Change-Id: Id805044b57289ee0f384b434aba1dbd2fd317e5b
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
SubmoduleUpdateCommand#setCallback should return 'this'
The other methods in this class follow the builder pattern, and
return 'this', allowing multiple method calls to be chained in a
single statement.
Update the setCallback method to do the same.
Change-Id: I4ddaacd6d50601f47f61eb6be8b62c8d59cce062
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
The other methods in this class follow the builder pattern, and
return 'this', allowing multiple method calls to be chained in a
single statement.
Update the setCallback method to do the same.
Change-Id: I0366d28bf66ba47f08ee7eee636d613c9fe079f5
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
ArchiveCommand: Create prefix entry with commit time
The cgit archive command creates a prefix (root) directory entry
in the archive file. That entry's time is set to the commit time.
This patch makes jgit's behavior consistent with with cgit:
prefix: hoge/ -> creates prefix directory "hoge/" entry.
prefix: hoge//// -> creates prefix directory "hoge/" entry.
prefix: hoge/foo -> does not create prefix directory entry, but for
each file/directory entry, prefix is added.
Change-Id: I2610e40ce37972c5f7456fdca6337e7fb07176e5
Signed-off-by: Yasuhiro Takagi <ytakagi@bea.hi-ho.ne.jp>
When running an automatic GC on a FileRepository, when the caller
passes a NullProgressMonitor, run the GC in a background thread. Use a
thread pool of size 1 to limit the number of background threads spawned
for background gc in the same application. In the next minor release we
can make the thread pool configurable.
In some cases, the auto GC limit is lower than the true number of
unreachable loose objects, so auto GC will run after every (e.g) fetch
operation. This leads to the appearance of poor fetch performance.
Since these GCs will never make progress (until either the objects
become referenced, or the two week timeout expires), blocking on them
simply reduces throughput.
In the event that an auto GC would make progress, it's still OK if it
runs in the background. The progress will still happen.
This matches the behavior of regular git.
Git (and now jgit) uses the lock file for gc.log to prevent simultaneous
runs of background gc. Further, it writes errors to gc.log, and won't
run background gc if that file is present and recent. If gc.log is too
old (according to the config gc.logexpiry), it will be ignored.
Change-Id: I3870cadb4a0a6763feff252e6eaef99f4aa8d0df
Signed-off-by: David Turner <dturner@twosigma.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
* master:
Fix out-of-bounds exception in RepoCommand#relative
Fix null return from FS.readPipe when command fails to launch
RenameDetector: Clarify rename limits <= 0
Remove unnecessary cast for DfsReader
Allow DfsReader to be subclassed
Track read IO for DfsReader
Fix javadoc of TooLargeObjectInPackException
Exclude refs/tags from bitmap commit selection
Change-Id: I9cd20ded108d2e5d81fa1f0c2cb9aa0eabe1f256
Fix null return from FS.readPipe when command fails to launch
When a command invoked from readPipe fails to launch (i.e. the exec call
fails due to a missing command executable), Process.start() throws,
which gets caught by the generic IOException handler, resulting in a
null return. This change detects this case and rethrows a
CommandFailedException instead.
Additionally, this change uses /bin/sh instead of bash for its posix
command failure test, to accomodate building in environments where bash
is unavailable.
Change-Id: Ifae51e457e5718be610c0a0914b18fe35ea7b008
Signed-off-by: Bryan Donlan <bdonlan@gmail.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Compute how much disk IO a DfsReader is performing, and how long the
sum of those operations took on this reader instance. Implementations
of DFS and interested applications can get the stats by calling the
new DfsReader.getIoStats() method at or after close().
Change-Id: If585741301f29182617933d6406d4a70497f2ca7
The API exception should have the same javadoc like the internal
exception org.eclipse.jgit.errors.TooLargeObjectInPackException
Change-Id: Ia7508c77609e53c8e808412ac523a93194648e49
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Commit db77610 ensured that all refs/tags commits are added to the
primary GC pack. It did that by adding all of the refs/tags commits
to the primary GC pack PackWriter's "interesting" object set.
Unfortunately, all commit objects in the "interesting" set are
selected as commits for which bitmap indices will be built. In a
repository like chromium with lots of tags, this changed the number of
bitmaps created from <700 to >10000. That puts huge memory pressure on
the GC task.
This change restores the original behavior of ignoring tags when
selecting commits for bitmaps.
In the "uninteresting" set, commits for refs/heads and refs/tags for
unannotated tags can not be differentiated. We instead identify
refs/tags commits by passing their ObjectIds as a new "noBitmaps"
parameter to the PackWriter.preparePack() methods.
PackWriterBitmapPreparer.setupTipCommitBitmaps() can then use that
"noBitmaps" parameter to exclude those commits.
Change-Id: Icd287c6b04fc1e48de773033fe432a9b0e904ac5
Signed-off-by: Terry Parker <tparker@google.com>
David Pursehouse
Dave Borowitz
Matthias Sohn
Nasser Grainawi
Christian Halstrick
Yasuhiro Takagi
David Turner
Han-Wen Nienhuys
Bryan Donlan
Zhen Chen
Shawn Pearce
Terry Parker