Matthias Sohn [Wed, 25 Nov 2020 16:00:09 +0000 (17:00 +0100)]
Ensure that GC#deleteOrphans respects pack lock
If pack or index files are guarded by a pack lock (.keep file)
deleteOrphans() should not touch the respective files protected by the
lock file. Otherwise it may interfere with PackInserter concurrently
inserting a new pack file and its index.
The problem was caused by the following race.
All mentioned files are located in "objects/pack/".
File endings relevant in "pack" dir:
.pack
.keep
.idx
.bitmap
When ReceivePack receives a pack file it executes the following steps:
ReceivePack.service():
receivePackAndCheckConnectivity():
receivePack():
receive the pack
parse the pack, returns packLock (.keep file)
PackInserter.flush():
write tmpPck file: "insert_<random>.pack"
write tmpIdx file: "insert_<random>.idx"
real pack name: "pack-<SHA1>.pack"
real index name: "pack-<SHA1>.idx"
atomic rename tmpPack to realPack
atomic rename tmpIdx to tmpIdx
execute commands
unlock pack by removing .keep file
trigger auto gc if enabled
When PackInserter.flush() renames the temporary pack to the final
"pack-xxx.pack" file the temporary pack index file "insert_xxx.idx"
has no matching .pack file with the same base name for a short interval.
If deleteOrphans() ran during that interval it deduced the pack index
file was orphaned. Subsequently the missing pack index caused
MissingObjectExceptions since objects contained in the pack couldn't be
looked up anymore.
Bug: https://bugs.chromium.org/p/gerrit/issues/detail?id=13544
Change-Id: I559c81e4b1d7c487f92a751bd78b987d32c98719 Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
David Pursehouse [Thu, 30 Jan 2020 23:38:24 +0000 (08:38 +0900)]
Fix string format parameter for invalidRefAdvertisementLine
The externalized error message added in f4fc640 ("BasePackConnection:
Check for expected length of ref advertisement", Dec 18, 2019) uses a
malformed string format. Since there is only one formatting argument,
it should be referenced with '{0}' rather than '{1}'.
Change-Id: Ibda864dfb0bb902fe07ae4bba73117b212046e8a Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
Matthias Sohn [Fri, 3 Jan 2020 17:16:42 +0000 (18:16 +0100)]
WindowCache: add metric for cached bytes per repository
Since ObjectDatabase and PackFile don't know their repository use the
packfile's grand-grand-parent directory as an identifier for the
repository the packfile resides in.
Remove metric for a repository if the number of cached bytes for the
repository drops to 0 in order to ensure the map of cached bytes per
repository doesn't contain repositories which have no data cached in the
WindowCache.
Change-Id: I969ab8029db0a292e7585cbb36ca0baa797da20b Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Matthias Sohn [Mon, 27 Jan 2020 22:00:57 +0000 (23:00 +0100)]
pgm daemon: fallback to user and system config if no config specified
If a config file is passed via option --config-file then use only the
options defined in that file. This helps to concisely configure the
daemon without side effects from global and system level git configs.
Otherwise fallback to user and system level configs.
Change-Id: I242de248f257579874ad0bfe4882a22502353b1f Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Matthias Sohn [Fri, 13 Dec 2019 00:18:12 +0000 (01:18 +0100)]
WindowCache: add option to use strong refs to reference ByteWindows
Java GC evicts all SoftReferences when the used heap size comes close to
the maximum heap size. This means peaks in heap memory consumption can
flush the complete WindowCache which was observed to have negative
impact on performance of upload-pack in Gerrit.
Hence add a boolean option core.packedGitUseStrongRefs to allow using
strong references to reference packfile pages cached in the WindowCache.
If this option is set to true Java gc can no longer flush the
WindowCache to free memory if the used heap comes close to the maximum
heap size. On the other hand this provides more predictable performance.
Bug: 553573
Change-Id: I9de406293087ab0fa61130c8e0829775762ece8d Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Patrick Hiesel [Thu, 9 Jan 2020 09:23:12 +0000 (10:23 +0100)]
Replace usage of ArrayIndexOutOfBoundsException in treewalk
Using exceptions during normal operations - for example with the
desire of expanding an array in the failure case - can have a
severe performance impact. When exceptions are instantiated,
a stack trace is collected. Generating stack trace can be expensive.
Compared to that, checking an array for length - even if done many
times - is cheap since this is a check that can run in just a
handful of CPU cycles.
Change-Id: Ifaf10623f6a876c9faecfa44654c9296315adfcb Signed-off-by: Patrick Hiesel <hiesel@google.com> Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Matthias Sohn [Sat, 4 Jan 2020 14:44:19 +0000 (15:44 +0100)]
SshSupport#runSshCommand: don't throw exception in finally block
The CommandFailedException which was thrown in finally block is silently
discarded [1]. Refactor this method to throw the exception after the
finally block.
This fixes the warning "Null comparison always yields false: The
variable failure can only be null at this location".
Matthias Sohn [Mon, 16 Dec 2019 14:22:08 +0000 (15:22 +0100)]
Ignore warnings for generated source code in org.eclipse.jgit.benchmark
The source code in the folder .apt_generated is generated by the JMH
code generator, so there's no point in raising any warnings as this
could only be fixed in the upstream code generator.
Change-Id: I882888e7bf924f9ae74182598fcb91671a5c9818 Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Matthias Sohn [Sat, 30 Nov 2019 02:38:13 +0000 (03:38 +0100)]
Enhance WindowCache statistics
Add the following statistics
- cache hit count and hit ratio
- cache miss count and miss ratio
- count of successful and failed loads
- rate of failed loads
- load, eviction and request count
- average and total load time
Use LongAdder instead of AtomicLong to implement counters in order to
improve scalability.
Optionally expose these metrics via JMX, they are registered with the
platform MBean server if the config option jmx.WindowCacheStats = true
in the user or system level git config.
Bug: 553573
Change-Id: Ia2d5246ef69b9c2bd594a23934424bc5800774aa Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Matthias Sohn [Sat, 3 Aug 2019 10:02:34 +0000 (12:02 +0200)]
JMH benchmark for SimpleLruCache
See [1] for JMH documentation and [2] how to use JMH in Eclipse.
The benchmarks pom currently cannot use the JGit parent pom due to an
ecj bug [3] regarding annotation processing. Hence for now do not
inherit from the JGit parent pom and copy the compiler plugin
configuration for javac from the parent pom.
After running the Maven build the benchmark can be run using Maven:
Do not rely on ArrayIndexOutOfBoundsException to detect end of input
In the Config#StringReader we relied on ArrayIndexOutOfBoundsException
to detect the end of the input. Creation of exception with (deep) stack
trace can significantly degrade performance in case when we read
thousands of config files, like in the case when Gerrit reads all
external ids from the NoteDb.
Use the buf.length to detect the end of the input.
Thomas Wolf [Thu, 12 Sep 2019 19:05:19 +0000 (21:05 +0200)]
WorkingTreeIterator: handle different timestamp resolutions
Older JGit stored only milliseconds timestamps in the index. Newer
JGit may get finer timestamps from the file system. This leads to
slow index diffs when a new JGit runs against an index produced
by older JGit because many timestamps will differ and JGit will
then do many content checks. See [1].
Handle this migration case by only comparing milliseconds if the
index entry has only millisecond precision.
The inverse may also occur; also compare only milliseconds if the
file timestamp has only millisecond precision.
Do the same also for microsecond resolution. On Windows, NTFS may
provide 100ns resolution and may be used by external programs writing
the index, but Java's WindowsFileAttributes may provide only
microseconds.
File timestamp precision in Java depends not only on the Java APIs
used by different JGit versions but may also change when running the
same Java code on different VMs. And of course the resolution may
vary among operating and file systems. Moreover, timestamp precision
in the index depends on the program that wrote the index. Canonical
git may use a different resolution, maybe even different between git
versions.
Change-Id: Idfd08606c883cb98787b2138f9baf0cc89a57b56 Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch> Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Matthias Sohn [Tue, 10 Sep 2019 14:08:45 +0000 (16:08 +0200)]
Fix WorkingTreeIterator.compareMetadata() for CheckStat.MINIMAL
If CheckStat is MINIMAL or timestamps have no nanosecond part
WorkingTreeIterator.compareMetaData only checks the second part of
timestamps and ignores nanoseconds which may have ended up in the index
by using native git.
we currently proceed comparing fileLastModified and cacheLastModified
with full precision which is wrong since we determined that we detected
reduced timestamp resolution.
Fix this and also handle smudged index entries for CheckStat.MINIMAL.
Change-Id: I6149885903ac63d79b42d234cc02aa4e19578f3c Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
David Pursehouse [Wed, 10 Oct 2018 01:53:35 +0000 (10:53 +0900)]
Bazel: Require minimum bazel version 0.17.1
Check the bazel version using the checker from bazel_skylib, and
require at least version 0.17.1 which is the minimum version that
does not suffer from the Java API mismatch issue [1].
The implementation is borrowed from the Gerrit project.
Matthias Sohn [Tue, 3 Sep 2019 14:02:44 +0000 (16:02 +0200)]
Merge branch 'stable-5.0' into stable-5.1
* stable-5.0:
Prepare 4.11.10-SNAPSHOT builds
JGit v4.11.9.201909030838-r
Bazel: Update bazlets to the latest master revision
Bazel: Remove FileTreeIteratorWithTimeControl from BUILD file
BatchRefUpdate: repro racy atomic update, and fix it
Delete unused FileTreeIteratorWithTimeControl
Fix RacyGitTests#testRacyGitDetection
Change RacyGitTests to create a racy git situation in a stable way
Silence API warnings
Change-Id: I172136a031ff0730e575327cafb3527c9650a71d Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Matthias Sohn [Tue, 3 Sep 2019 13:54:54 +0000 (15:54 +0200)]
Merge branch 'stable-4.11' into stable-5.0
* stable-4.11:
Prepare 4.11.10-SNAPSHOT builds
JGit v4.11.9.201909030838-r
Bazel: Update bazlets to the latest master revision
Bazel: Remove FileTreeIteratorWithTimeControl from BUILD file
BatchRefUpdate: repro racy atomic update, and fix it
Delete unused FileTreeIteratorWithTimeControl
Fix RacyGitTests#testRacyGitDetection
Change RacyGitTests to create a racy git situation in a stable way
Silence API warnings
Change-Id: Ifb6a4dbea2f48fd2ffa66eb737d61920aefedfbd Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Matthias Sohn [Tue, 3 Sep 2019 12:23:29 +0000 (14:23 +0200)]
Merge branch 'stable-4.10' into stable-4.11
* stable-4.10:
Bazel: Update bazlets to the latest master revision
Bazel: Remove FileTreeIteratorWithTimeControl from BUILD file
BatchRefUpdate: repro racy atomic update, and fix it
Delete unused FileTreeIteratorWithTimeControl
Fix RacyGitTests#testRacyGitDetection
Change RacyGitTests to create a racy git situation in a stable way
Silence API warnings
Change-Id: If672b4f0c350f4e8ff7e1e706485cffd8137236d Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Matthias Sohn [Tue, 3 Sep 2019 11:24:28 +0000 (13:24 +0200)]
Merge branch 'stable-4.9' into stable-4.10
* stable-4.9:
BatchRefUpdate: repro racy atomic update, and fix it
Delete unused FileTreeIteratorWithTimeControl
Fix RacyGitTests#testRacyGitDetection
Change RacyGitTests to create a racy git situation in a stable way
Silence API warnings
Change-Id: Id5bf44645655fca40ad22bb1f1ad20a7c2e8f6db Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Han-Wen Nienhuys [Sat, 31 Aug 2019 19:33:58 +0000 (21:33 +0200)]
BatchRefUpdate: repro racy atomic update, and fix it
PackedBatchRefUpdate was creating a new packed-refs list that was
potentially unsorted. This would be papered over when the list was
read back from disk in parsePackedRef, which detects unsorted ref
lists on reading, and sorts them. However, the BatchRefUpdate also
installed the new (unsorted) list in-memory in
RefDirectory#packedRefs.
With the timestamp granularity code committed to stable-5.1, we can
more often accurately decide that the packed-refs file is clean, and
will return the erroneous unsorted data more often. Unluckily timed
delays also cause the file to be clean, hence this problem was
exacerbated under load.
The symptom is that refs added by a BatchRefUpdate would stop being
visible directly after they were added. In particular, the Gerrit
integration tests uses BatchRefUpdate in its setup for creating the
Admin group, and then tries to read it out directly afterward.
The tests recreates one failure case. A better approach would be to
revise RefList.Builder, so it detects out-of-order lists and
automatically sorts them.
Fixes https://bugs.eclipse.org/bugs/show_bug.cgi?id=548716 and
https://bugs.chromium.org/p/gerrit/issues/detail?id=11373.
Matthias Sohn [Tue, 18 Jun 2019 09:32:59 +0000 (11:32 +0200)]
Fix RacyGitTests#testRacyGitDetection
This test case assumed file system timestamp resolution of 1 second. On
filesystems with a finer resolution this test fails since the index
entry is only smudged if the file index entry's lastModified and the
lastModified of the git index itself are within the same filesystem
timer tick. Fix this by ensuring that these timestamps are identical
which should work for any filesystem timer resolution.
Bug: 548188
Change-Id: Id84d59e1cfeb48fa008f8f27f2f892c4f73985de Signed-off-by: Matthias Sohn <matthias.sohn@sap.com> Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
(cherry picked from commit 1159f9dd7c80a53c2509cd75d997a6afed37f9a6)
Matthias Sohn [Mon, 26 Aug 2019 20:43:11 +0000 (22:43 +0200)]
Return a new instance from openSystemConfig and openUserConfig
Move the handling of cached user and system config to getSystemConfig
and getUserConfig methods and revert the implementation of
openSystemConfig and openUserConfig to the old stateless
implementation.
This ensures the open methods respect the passed-in parent config, which
may be different on each invocation. Additionally, returning a new
instance matches the behavior of the previous implementation of the
default system reader, which downstream callers may be depending on.
Move the implementation of the new caching methods getSystemConfig and
getUserConfig up to SystemReader. This avoids that we break the ABI for
subclasses of SystemReader.
Also see [1] which fixed a similar problem with Gerrit's custom
SystemReader.
Matthias Sohn [Tue, 20 Aug 2019 22:29:45 +0000 (00:29 +0200)]
Avoid sign extension when comparing mtime with Instant#getEpochSecond
Ensure we use the same type when comparing seconds since the epoch.
This does not prevent that in 2038 timestamps in seconds since the epoch
stored in a 32 bit integer will overflow. Integer.MAX_VALUE translates
to 2038-01-19T03:14:07Z. After this date we'll have an issue since we
store seconds since the epoch in a 32 bit integer in some places.
Bug: 319142
Change-Id: If0c03003d40b480f044686e2f7a2f62c9f4e2fe1 Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Michael Keppler [Tue, 20 Aug 2019 14:09:12 +0000 (16:09 +0200)]
Fix deprecation in DirCache caused by Instant based DirCacheEntry
Replace the two int variables smudge_s and smudge_ns by an Instant and
use the new method DirCacheEntry.mightBeRacilyClean(Instant).
Change-Id: Id70adbb0856a64909617acf65da1bae8e2ae934a Signed-off-by: Michael Keppler <Michael.Keppler@gmx.de> Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Matthias Sohn [Wed, 14 Aug 2019 23:25:28 +0000 (01:25 +0200)]
Cache user global and system-wide git configurations
So far the git configuration and the system wide git configuration were
always reloaded when jgit accessed these global configuration files to
access global configuration options which are not in the context of a
single git repository. Cache these configurations in SystemReader and
only reload them if their file metadata observed using FileSnapshot
indicates a modification.
Change-Id: I092fe11a5d95f1c5799273cacfc7a415d0b7786c Signed-off-by: Matthias Sohn <matthias.sohn@sap.com> Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
Matthias Sohn [Sun, 11 Aug 2019 00:43:02 +0000 (02:43 +0200)]
Avoid setup and saving FileStoreAttributes compete for ~/.gitconfig lock
FS determines FileStore attributes in a background thread and tries to
save the results to the global git configuration. This competed with
LocalDiskRepositoryTestCase#setup trying to save changes to the same
file requiring the same lock. This frequently led to one of the threads
failing to acquire the lock.
Fix this by first initiating determination of FileStore attributes which
then uses a MockSystemReader not using a userConfig stored to disk which
avoids this race for the lock.
Change-Id: I30fcd96bc15100f8ef9b2a9eb3320bb5ace97c67 Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Matthias Sohn [Mon, 12 Aug 2019 15:40:39 +0000 (17:40 +0200)]
Improve retry handling when saving FileStoreAttributes fails
- fix handling of interrupts in FileStoreAttributes#saveToConfig
- increase retry wait time to 100ms
- don't wait after last retry
- dont retry if failure is caused by another exception than
LockFailedException
Change-Id: I108c012717d2bcce71f2c6cb9cf0879de704ebc2 Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Make supportsAtomicCreateNewFile return true as default
The method org.eclipse.jgit.util.FS.supportsAtomicCreateNewFile()
should default to true as mentioned in docs [1]
org.eclipse.jgit.util.FS_POSIX.supportsAtomicCreateNewFile() method
will set the value to false if the git config
core.supportsatomiccreatenewfile is not set.
It should default to true if the configuration is undefined.
Matthias Sohn [Mon, 12 Aug 2019 10:02:59 +0000 (12:02 +0200)]
Update orbit to R20190602212107-2019-06 to enable backports from master
update
- org.apache.httpcomponents.httpclient to 4.5.6.v20190503-0009
- org.apache.httpcomponents.httpcore to 4.4.10.v20190123-2214
- com.jcraft.jsch" version to 0.1.55.v20190404-1902
- org.mockito to 2.23.0.v20190527-1420
add its dependencies
- net.bytebuddy.byte-buddy 1.9.0.v20181107-1410
- net.bytebuddy.byte-buddy-agent 1.9.0.v20181106-1534
- org.objenesis to 2.6.0.v20180420-1519
FS#getFileStoreAttributes used the real userConfig and not the mocked
one. This led to test errors when running tests with Bazel since it
sandboxes tests which prevents they can write to ~/.gitconfig.
Fix this by first preparing the MockedSystemReader and the mocked config
before calling FS#getFileStoreAttributes.
Also fix ConfigTest which broke due to this change since it inherits
from LocalDiskRepositoryTestCase and calls its setup method which was
changed here. We can no longer assert by comparing plain text since FS
adds FileStoreAttributes to the mocked userConfig. Also the default
options seen by this test changed since we now use a mocked config.
Change-Id: I76bc7c94953fe979266147d3b309a68dda9d4dfe Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Matthias Sohn [Sat, 10 Aug 2019 21:34:58 +0000 (23:34 +0200)]
Ensure we use MockSystemReader in tests
If we use the default system reader FileStoreAttributes cannot persist
attributes in userConfig when tests run in Bazel due to sandboxing.
Hence we need to ensure that all tests use MockSystemReader (and
especially a mocked userConfig).
Change-Id: Ic1ad8e2ec5a150c5433434a5f6667d6c4674c87d Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Matthias Sohn [Sat, 10 Aug 2019 21:28:07 +0000 (23:28 +0200)]
Remove FileBasedConfig.load(boolean) introduced in d45219ba
We can't add this method to the super class StoredConfig since that
abstracts from filesystem storage. MockSystemReader.MockConfig is a
StoredConfig and is also used by tests for dfs based storage. Hence
remove this leaky abstraction.
This implies we always use the fallback FileStoreAttributes which means
a config file modification is considered racy within the first 2
seconds. This should not be an issue since typically configs change
rarely and re-reading a config within the racy period is relatively
cheap since configs are small.
Change-Id: Ia2615addc24a7cadf3c566ee842c6f4f07e159a5 Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
projects / jgit.git / log