Commit Graph

7136 Commits

Author SHA1 Message Date
Matthias Sohn a52b331d71 Fix formatting and add missing braces in Repository#stripWorkDir
Change-Id: I601d917f3741e0207a8ee7a365d9c2dea6422401
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-08-08 14:42:14 +02:00
Matthias Sohn 400bfd6665 Repository: fix reference comparison of Files
Change-Id: Ib46ea2c0d5039c88b4fc59723135c503a8c950ce
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-08-08 14:41:16 +02:00
David Pursehouse 6370098e54 MergeAlgorithm: Suppress Error Prone warning about reference equality
Error Prone reports:

  [ReferenceEquality] Comparison using reference equality instead of
  value equality

The END_EDIT instance is used as a marker, and thus it's OK to use
a reference equality comparison. Factor the comparison to a method
and add a suppression.

Change-Id: I7d9dc1fa21f46c984787056b0b5d163e313026a6
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
2019-08-08 14:34:24 +02:00
David Pursehouse 72ae089206 Fix NarrowingCompoundAssignment warnings from Error Prone
Error Prone reports:

  [NarrowingCompoundAssignment] Compound assignments from long to int
  hide lossy casts

and

  [NarrowingCompoundAssignment] Compound assignments from int to byte
  hide lossy casts

  See https://errorprone.info/bugpattern/NarrowingCompoundAssignment

Fix the warnings by adding explicit casts or changing types as
necessary.

Now that all occurrences of the warning are fixed, increase its
severity to ERROR.

Change-Id: Idb3670e6047b146ae37daee07212ff9455512623
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
2019-08-08 14:28:27 +02:00
Thomas Wolf aefb11298c FS_POSIX: handle Files.getFileStore() failures
Android unconditionally throws a SecurityException;[1] getFileStore()
is not supported. Catch the exception and don't attempt the hard-
linking atomic file mechanism.

[1] https://android.googlesource.com/platform/libcore/+/21e6175e25

Bug: 548947
Change-Id: Idfba2d9dbcbc80ea15ab2ae7889e5142444c1581
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
2019-08-08 14:14:38 +02:00
Matthias Sohn f54db4a857 Merge branch 'stable-5.3' into stable-5.4
* stable-5.3:
  Fix OpenSshConfigTest#config
  FileSnapshot: fix bug with timestamp thresholding
  In LockFile#waitForStatChange wait in units of file time resolution
  Cache FileStoreAttributeCache per directory
  Fix FileSnapshot#save(long) and FileSnapshot#save(Instant)
  Persist minimal racy threshold and allow manual configuration
  Measure minimum racy interval to auto-configure FileSnapshot
  Reuse FileUtils to recursively delete files created by tests
  Fix FileAttributeCache.toString()
  Add test for racy git detection in FileSnapshot
  Repeat RefDirectoryTest.testGetRef_DiscoversModifiedLoose 100 times
  Fix org.eclipse.jdt.core.prefs of org.eclipse.jgit.junit
  Add missing javadoc in org.eclipse.jgit.junit
  Enhance RepeatRule to report number of failures at the end
  Fix FileSnapshotTests for filesystem with high timestamp resolution
  Retry deleting test files in FileBasedConfigTest
  Measure filesystem timestamp resolution already in test setup
  Refactor FileSnapshotTest to use NIO APIs
  Measure stored timestamp resolution instead of time to touch file
  Handle CancellationException in FileStoreAttributeCache
  Fix FileSnapshot#saveNoConfig
  Use Instant for smudge time in DirCache and DirCacheEntry
  Use Instant instead of milliseconds for filesystem timestamp handling
  Workaround SecurityException in FS#getFsTimestampResolution
  Fix NPE in FS$FileStoreAttributeCache.getFsTimestampResolution
  FS: ignore AccessDeniedException when measuring timestamp resolution
  Add debug trace for FileSnapshot
  Use FileChannel.open to touch file and set mtime to now
  Persist filesystem timestamp resolution and allow manual configuration
  Increase bazel timeout for long running tests
  Bazel: Fix lint warning flagged by buildifier
  Update bazlets to latest version
  Bazel: Add missing dependencies for ArchiveCommandTest
  Bazel: Remove FileTreeIteratorWithTimeControl from BUILD file
  Add support for nanoseconds and microseconds for Config#getTimeUnit
  Optionally measure filesystem timestamp resolution asynchronously
  Delete unused FileTreeIteratorWithTimeControl
  FileSnapshot#equals: consider UNKNOWN_SIZE
  Timeout measuring file timestamp resolution after 2 seconds
  Fix RacyGitTests#testRacyGitDetection
  Change RacyGitTests to create a racy git situation in a stable way
  Deprecate Constants.CHARACTER_ENCODING in favor of StandardCharsets.UTF_8
  Fix non-deterministic hash of archives created by ArchiveCommand
  Update Maven plugins ecj, plexus, error-prone
  Update Maven plugins and cleanup Maven warnings
  Make inner classes static where possible
  Fix API problem filters

Change-Id: Iec3ad6ccc194582cb844310dc172c3103dae4457
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-08-08 13:24:14 +02:00
Matthias Sohn 718555518d Merge branch 'stable-5.2' into stable-5.3
* stable-5.2:
  Fix OpenSshConfigTest#config
  FileSnapshot: fix bug with timestamp thresholding
  In LockFile#waitForStatChange wait in units of file time resolution
  Cache FileStoreAttributeCache per directory
  Fix FileSnapshot#save(long) and FileSnapshot#save(Instant)
  Persist minimal racy threshold and allow manual configuration
  Measure minimum racy interval to auto-configure FileSnapshot
  Reuse FileUtils to recursively delete files created by tests
  Fix FileAttributeCache.toString()
  Add test for racy git detection in FileSnapshot
  Repeat RefDirectoryTest.testGetRef_DiscoversModifiedLoose 100 times
  Fix org.eclipse.jdt.core.prefs of org.eclipse.jgit.junit
  Add missing javadoc in org.eclipse.jgit.junit
  Enhance RepeatRule to report number of failures at the end
  Fix FileSnapshotTests for filesystem with high timestamp resolution
  Retry deleting test files in FileBasedConfigTest
  Measure filesystem timestamp resolution already in test setup
  Refactor FileSnapshotTest to use NIO APIs
  Measure stored timestamp resolution instead of time to touch file
  Handle CancellationException in FileStoreAttributeCache
  Fix FileSnapshot#saveNoConfig
  Use Instant for smudge time in DirCache and DirCacheEntry
  Use Instant instead of milliseconds for filesystem timestamp handling
  Workaround SecurityException in FS#getFsTimestampResolution
  Fix NPE in FS$FileStoreAttributeCache.getFsTimestampResolution
  FS: ignore AccessDeniedException when measuring timestamp resolution
  Add debug trace for FileSnapshot
  Use FileChannel.open to touch file and set mtime to now
  Persist filesystem timestamp resolution and allow manual configuration
  Increase bazel timeout for long running tests
  Bazel: Fix lint warning flagged by buildifier
  Update bazlets to latest version
  Bazel: Add missing dependencies for ArchiveCommandTest
  Bazel: Remove FileTreeIteratorWithTimeControl from BUILD file
  Add support for nanoseconds and microseconds for Config#getTimeUnit
  Optionally measure filesystem timestamp resolution asynchronously
  Delete unused FileTreeIteratorWithTimeControl
  FileSnapshot#equals: consider UNKNOWN_SIZE
  Timeout measuring file timestamp resolution after 2 seconds
  Fix RacyGitTests#testRacyGitDetection
  Change RacyGitTests to create a racy git situation in a stable way
  Deprecate Constants.CHARACTER_ENCODING in favor of
StandardCharsets.UTF_8
  Fix non-deterministic hash of archives created by ArchiveCommand
  Update Maven plugins ecj, plexus, error-prone
  Update Maven plugins and cleanup Maven warnings
  Make inner classes static where possible
  Fix API problem filters

Change-Id: I238adfd3080a5fed9d64c3c757297da6ea893918
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-08-08 13:04:38 +02:00
Matthias Sohn 0046b2a8fe Merge branch 'stable-5.1' into stable-5.2
* stable-5.1:
  Fix OpenSshConfigTest#config
  FileSnapshot: fix bug with timestamp thresholding
  In LockFile#waitForStatChange wait in units of file time resolution
  Cache FileStoreAttributeCache per directory
  Fix FileSnapshot#save(long) and FileSnapshot#save(Instant)
  Persist minimal racy threshold and allow manual configuration
  Measure minimum racy interval to auto-configure FileSnapshot
  Reuse FileUtils to recursively delete files created by tests
  Fix FileAttributeCache.toString()
  Add test for racy git detection in FileSnapshot
  Repeat RefDirectoryTest.testGetRef_DiscoversModifiedLoose 100 times
  Fix org.eclipse.jdt.core.prefs of org.eclipse.jgit.junit
  Add missing javadoc in org.eclipse.jgit.junit
  Enhance RepeatRule to report number of failures at the end
  Fix FileSnapshotTests for filesystem with high timestamp resolution
  Retry deleting test files in FileBasedConfigTest
  Measure filesystem timestamp resolution already in test setup
  Refactor FileSnapshotTest to use NIO APIs
  Measure stored timestamp resolution instead of time to touch file
  Handle CancellationException in FileStoreAttributeCache
  Fix FileSnapshot#saveNoConfig
  Use Instant for smudge time in DirCache and DirCacheEntry
  Use Instant instead of milliseconds for filesystem timestamp handling
  Workaround SecurityException in FS#getFsTimestampResolution
  Fix NPE in FS$FileStoreAttributeCache.getFsTimestampResolution
  FS: ignore AccessDeniedException when measuring timestamp resolution
  Add debug trace for FileSnapshot
  Use FileChannel.open to touch file and set mtime to now
  Persist filesystem timestamp resolution and allow manual configuration
  Increase bazel timeout for long running tests
  Bazel: Fix lint warning flagged by buildifier
  Update bazlets to latest version
  Bazel: Add missing dependencies for ArchiveCommandTest
  Bazel: Remove FileTreeIteratorWithTimeControl from BUILD file
  Add support for nanoseconds and microseconds for Config#getTimeUnit
  Optionally measure filesystem timestamp resolution asynchronously
  Delete unused FileTreeIteratorWithTimeControl
  FileSnapshot#equals: consider UNKNOWN_SIZE
  Timeout measuring file timestamp resolution after 2 seconds
  Fix RacyGitTests#testRacyGitDetection
  Change RacyGitTests to create a racy git situation in a stable way
  Deprecate Constants.CHARACTER_ENCODING in favor of StandardCharsets.UTF_8
  Fix non-deterministic hash of archives created by ArchiveCommand
  Update Maven plugins ecj, plexus, error-prone
  Update Maven plugins and cleanup Maven warnings
  Make inner classes static where possible
  Fix API problem filters

Change-Id: Ia57385b2a60f48a5317c8d723721c235d7043a84
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-08-08 11:54:56 +02:00
Matthias Sohn 5a88815b1c Fix OpenSshConfigTest#config
- use FS.DETECTED instead of db.getFS() since the ssh config is
typically in a different place than the repository, the same is used in
OpenSshConfig
- reduce unnecessary repeated writes by introducing wait for one tick of
the file time resolution

Change-Id: Ifac915e97ff420ec5cf8e2f162e351f9f51b6b14
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-08-08 10:10:12 +02:00
Han-Wen Nienhuys e60b9e1879 FileSnapshot: fix bug with timestamp thresholding
Increase the safety factor to 2.5x for extra safety if max of measured
timestamp resolution and measured minimal racy threshold is < 100ms, use
1.25 otherwise since for large filesystem resolution values the
influence of finite resolution of the system clock should be negligible.

Before, not yet using the newly introduced minRacyThreshold measurement,
the threshold was 1.1x FS resolution, and we could issue the
following sequence of events,

  start
  create-file
  read-file (currentTime)
  end

which had the following timestamps:

  create-file 1564589081998
  start 1564589082002
  read 1564589082003
  end 1564589082004

In this case, the difference between create-file and read is 5ms,
which exceeded the 4ms FS resolution, even though the events together
took just 2ms of runtime.

Reproduce with:
  bazel test --runs_per_test=100 \
    //org.eclipse.jgit.test:org_eclipse_jgit_internal_storage_file_FileSnapshotTest

The file system timestamp resolution is 4ms in this case.

This code assumes that the kernel and the JVM use the same clock that
is synchronized with the file system clock. This seems plausible,
given the resolution of System.currentTimeMillis() and the latency for
a gettimeofday system call (typically ~1us), but it would be good to
justify this with specifications.

Also cover a source of flakiness: if the test runs under extreme load,
then we could have

  start
  create-file
  <long delay>
  read
  end

which would register as an unmodified file. Avoid this by skipping the
test if end-start is too big.

[msohn]:
- downported from master to stable-5.1
- skip test if resolution is below 10ms
- adjust safety factor to 1.25 for resolutions above 100ms

Change-Id: I87d2cf035e01c44b7ba8364c410a860aa8e312ef
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-08-07 13:56:08 +02:00
Matthias Sohn 3b368d5578 In LockFile#waitForStatChange wait in units of file time resolution
Since we now measure file time resolution we can use it to replace the
hard coded wait time of 25ms. FileSnapshot#equals will return true until
the mtime of the old (o) and the new FileSnapshot (n) differ by at least
one  file time resolution.

Change-Id: Icb713a80ce9eb929242ed083406bfb6650c72223
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-08-07 13:21:39 +02:00
Matthias Sohn 6857138e19 Cache FileStoreAttributeCache per directory
Cache FileStoreAttributeCache entries since looking up FileStore for a
file may be expensive on some platforms.

Implement a simple LRU cache based on ConcurrentHashMap using a simple
long counter to order access to cache entries.

Change-Id: I4881fa938ad2f17712c05da857838073a2fc4ddb
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Signed-off-by: Marc Strapetz <marc.strapetz@syntevo.com>
Also-By: Marc Strapetz <marc.strapetz@syntevo.com>
2019-08-06 14:54:39 +02:00
Matthias Sohn 275f3da783 Fix FileSnapshot#save(long) and FileSnapshot#save(Instant)
Use the fallback timestamp resolution as already described in the
javadoc of these methods. Using zero file timestamp resolution doesn't
make sense.

Change-Id: Iaad2a0f99c3be3678e94980a0a368181b6aed38c
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-08-06 14:54:39 +02:00
Matthias Sohn d45219baac Persist minimal racy threshold and allow manual configuration
To enable persisting the minimal racy threshold per FileStore add a
new config option to the user global git configuration:

- Config section is "filesystem"
- Config subsection is concatenation of
  - Java vendor (system property "java.vendor")
  - Java version (system property "java.version")
  - FileStore's name, on Windows we use the attribute volume:vsn instead
    since  the name is not necessarily unique.
  - separated by '|'
  e.g.
    "AdoptOpenJDK|1.8.0_212-b03|/dev/disk1s1"
  The same prefix is used as for filesystem timestamp resolution, so
  both values are stored in the same config section
- The config key for minmal racy threshold is "minRacyThreshold" as a
  time value, supported time units are those supported by
  DefaultTypedConfigGetter#getTimeUnit
- measure for 3 seconds to limit runtime which depends on hardware, OS
  and Java version being used

If the minimal racy threshold is configured for a given FileStore the
configured value is used instead of measuring it.

When the minimal racy threshold was measured it is persisted in the user
global git configuration.

Rename FileStoreAttributeCache to FileStoreAttributes since this class
is now declared public in order to enable exposing all attributes in one
object.

Example:

[filesystem "AdoptOpenJDK|11.0.3|/dev/disk1s1"]
	timestampResolution = 7000 nanoseconds
	minRacyThreshold = 3440 microseconds

Change-Id: I22195e488453aae8d011b0a8e3276fe3d99deaea
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Also-By: Marc Strapetz <marc.strapetz@syntevo.com>
2019-08-06 14:54:39 +02:00
Matthias Sohn 5911521ba6 Measure minimum racy interval to auto-configure FileSnapshot
By running FileSnapshotTest#detectFileModified we found that the sum of
measured filesystem timestamp resolution and measured clock resolution
may yield a too small interval after a file has been modified which we
need to consider racily clean. In our tests we didn't find this behavior
on all systems we tested on, e.g. on MacOS using APFS and Java 8 and 11
this effect was not observed.

On Linux (SLES 15, kernel 4.12.14-150.22-default) we collected the
following test results using Java 8 and 11:

In 23-98% of 10000 test runs (depending on filesystem type and Java
version) the test failed, which means the effective interval which needs
to be considered racily clean after a file was modified is larger than
the measured file timestamp resolution.

"delta" is the observed interval after a file has been modified but
FileSnapshot did not yet detect the modification:

"resolution" is the measured sum of file timestamp resolution and clock
resolution seen in Java.

Java version    filesystem  failures resolution  min delta   max delta
1.8.0_212-b04   btrfs	    98.6%       1 ms        3.6 ms      6.6 ms
1.8.0_212-b04   ext4        82.6%       3 ms        1.1 ms      4.1 ms
1.8.0_212-b04   xfs         23.8%       4 ms        3.7 ms      3.9 ms
1.8.0_212-b04   zfs         23.1%       3 ms        4.8 ms      5.0 ms
11.0.3+7        btrfs       98.1%       3 us        0.7 ms      4.7 ms
11.0.3+7        ext4        98.1%       6 us        0.7 ms      4.7 ms
11.0.3+7        xfs         98.5%       7 us        0.1 ms      8.0 ms
11.0.3+7        zfs         98.4%       7 us        0.7 ms      5.2 ms

Mac OS
1.8.0_212       APFS        0%          1 s
11.0.3+7        APFS        0%          6 us

The observed delta is not distributed according to a normal gaussian
distribution but rather random in the observed range between "min delta"
and "max delta".

Run this test after measuring file timestamp resolution in
FS.FileAttributeCache to auto-configure JGit since it's unclear what
mechanism is causing this effect.

In FileSnapshot#isRacyClean use the maximum of the measured timestamp
resolution and the measured "delta" as explained above to decide if a
given FileSnapshot is to be considered racily clean. Add a 30% safety
margin to ensure we are on the safe side.

Change-Id: I1c8bb59f6486f174b7bbdc63072777ddbe06694d
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-08-06 14:54:35 +02:00
Matthias Sohn 902935c38c Reuse FileUtils to recursively delete files created by tests
Replace redundant complex implementation of recursive delete by the one
in FileUtils.

Change-Id: Iced1468b96c4f32381a9cf0c651b2bf6a9a9af35
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-26 15:53:33 +02:00
Matthias Sohn d17efe880d Fix FileAttributeCache.toString()
We should not list the complete cache but only show the cache entry at
hand.

Change-Id: I22be2a4dcbf0145155e23f2389bfcf5662cf23a6
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-26 15:53:29 +02:00
Matthias Sohn 130aa31262 Add test for racy git detection in FileSnapshot
Repeat the test 10000 times to get statistics if measured
fsTimestampResolution is working in practice to detect racy git
situations.

Add a class to compute statistics for this test. Log delta between
lastModified and time when FileSnapshot failed to detect modification.
This happens if the racy git limit determined by measuring filesystem
timestamp resolution and clock resolution is too small. If it would be
correct FileSnapshot would always detect modification or mark it
modified if time since modification is smaller than the racy git limit.

Change-Id: Iabe7af1a7211ca58480f8902d4fa4e366932fc77
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-26 15:49:38 +02:00
Matthias Sohn de6df3bdd9 Repeat RefDirectoryTest.testGetRef_DiscoversModifiedLoose 100 times
This should help to detect if measured fsTimeResolution is too small.

Change-Id: Id1f54dbdedb52b17859904e47776fa3a5887b8be
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-24 16:21:54 +02:00
Matthias Sohn 773cbb5f63 Fix org.eclipse.jdt.core.prefs of org.eclipse.jgit.junit
Use the same JDT core settings as used in org.eclipse.jgit but ignore
non-externalized strings.

Change-Id: If30013c76a197e571601a8abc882ac6a99592374
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-24 16:21:53 +02:00
Matthias Sohn 376c20f454 Add missing javadoc in org.eclipse.jgit.junit
Change-Id: Ib709ef050bec31c87f542fb2cc977863dda93ef9
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-24 16:21:48 +02:00
Matthias Sohn ba5d13ed42 Enhance RepeatRule to report number of failures at the end
In order to enable counting how frequently a test fails if repeated add
option abortOnFailure. If it is true the test aborts on the first
failure. Otherwise it runs the configured number of repetitions and, if
there was any failure, throws a RepeatException reporting how many of
the test repetitions failed.

Change-Id: Ic47de44d4a6273fddf04b9993ad989903efb40c3
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-19 14:45:56 +02:00
Matthias Sohn 9eff45e4f2 Fix FileSnapshotTests for filesystem with high timestamp resolution
When filesystem timestamp resolution is very high some tests don't work
since runtime of the test setup is too long to reach a racily clean
FileSnapshot. Hence skip these tests when timestamp resolution is higher
than 10 millisecond.

Change-Id: Ie47dd10eda22037b5c1ebff6b6becce0654ea807
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-19 14:45:56 +02:00
Matthias Sohn bce4ac97fa Retry deleting test files in FileBasedConfigTest
Change-Id: I304b2b6f2e39f72f620bba53aead60256aed3660
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-19 14:45:55 +02:00
Matthias Sohn eda2e95fa8 Measure filesystem timestamp resolution already in test setup
This helps to avoid some time critical tests can't prepare the test
fixture intended since measuring timestamp resolution takes time.

Change-Id: Ib34023e682a106070ca97e98ef16789a4dfb97b4
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-19 14:45:55 +02:00
Matthias Sohn 93144f1438 Refactor FileSnapshotTest to use NIO APIs
- use Path instead of File
- create test directories, files and output stream using Files methods
- delete unused list "files"

Change-Id: I8c5c601eca9f613efb5618d33b262277df92a06a
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-19 14:45:55 +02:00
Matthias Sohn 99d351d0cb Measure stored timestamp resolution instead of time to touch file
Measure granularity of timestamps stored in the filesystem by setting
and then getting lastModified timestamp until the read value changed.
Increase increment exponentially to limit number of iterations starting
with 1 microsecond since Java's FileTime (up to Java 12) truncates
timestamps to 1 microsecond resolution. The chosen algorithm yields 2000
steps between 1 ms and 2.5 s.

Also measure clock resolution and add that for the total timestamp
resolution. This avoids systematic measurement errors introduced by
doing IO to touch a file.

Change-Id: I9b37138619422452373e298d9d8c7cb2c384db3f
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-19 14:45:55 +02:00
Matthias Sohn 37f7679fc9 Handle CancellationException in FileStoreAttributeCache
Change-Id: If5985fbf04f630b1d72a1bafd508e0e15e1436be
2019-07-19 14:45:55 +02:00
Matthias Sohn 72d6e304b8 Fix FileSnapshot#saveNoConfig
We should not use configuration when creating FileSnapshot when
accessing FileBasedConfig.

Change-Id: Ic521632870f18bb004751642b9d30648dd94049a
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-19 14:45:55 +02:00
Matthias Sohn d8d9427277 Use Instant for smudge time in DirCache and DirCacheEntry
Change-Id: I98050a51baf4726c5717ef62ce7f026173666bdf
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-18 03:36:18 +02:00
Matthias Sohn 95e8264cc8 Use Instant instead of milliseconds for filesystem timestamp handling
This enables higher file timestamp resolution on filesystems like ext4,
Mac APFS (1ns) or NTFS (100ns) providing high timestamp resolution on
filesystem level.

Note:
- on some OSes Java 8,9 truncate milliseconds, see
https://bugs.openjdk.java.net/browse/JDK-8177809, fixed in Java 10
- UnixFileAttributes truncates timestamp resolution to microseconds when
converting the internal representation to FileTime exposed in the API,
see https://bugs.openjdk.java.net/browse/JDK-8181493
- WindowsFileAttributes also provides only microsecond resolution

Change-Id: I25ffff31a3c6f725fc345d4ddc2f26da3b88f6f2
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-18 03:27:52 +02:00
Matthias Sohn 4db39f5074 Workaround SecurityException in FS#getFsTimestampResolution
On Android FS#getFsTimestampResolution always throws a
SecurityException, handle this by falling back to the fallback timestamp
resolution.

Bug: 548947
Change-Id: I0ee6cb3c20e189bdc8d488434a930427ad6f2df2
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-17 09:42:15 +02:00
Matthias Sohn 79ede0c322 Fix NPE in FS$FileStoreAttributeCache.getFsTimestampResolution
Bug: 548682
Change-Id: I48840d3a68cf1db92c056d218a0d5ed0b9ea4c45
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-17 09:42:14 +02:00
Matthias Sohn be66222d1a FS: ignore AccessDeniedException when measuring timestamp resolution
It seems on cygwin creating a file under a writable directory can fail
with AccessDeniedException. Log a warning in this case and fallback to
worst case timestamp resolution of 2 seconds.

Bug: 548648
Change-Id: Ic50c31ce9dc9ccadd4db5247df929418ac62d45c
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-17 09:42:14 +02:00
Matthias Sohn 09fec1a102 Add debug trace for FileSnapshot
Checking lastModified is time critical hence debug trace is the only way
to analyze issues since debugging is impractical.

Also add configuration for buffering of log4j output to reduce runtime
impact when debug trace is on. Limit buffer to 1MiB and comment this
configuration out since we may not always want to use buffering.

Change-Id: Ib1a0537b67c8dc3fac994a77b42badd974ce6c97
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-17 09:42:14 +02:00
Matthias Sohn 8a0ed8a004 Use FileChannel.open to touch file and set mtime to now
Use options
- StandardOpenOption.CREATE to create touched file if not existing
- StandardOpenOption.SYNC to enforce synch of data and meta data changes
- StandardOpenOption.WRITE

Also set mtime explicitly in FileUtils#touch to the current system time.
This should fix that the previous implementation didn't work on
- locally cached Windows network share (CSC-CACHE filesystem) mapped as
a drive
- nfsv4 mounts on Linux
and that it didn't create unborn file like Linux command "touch".
Apache common's and Guava's touch() use the same approach.

Immediately after creating the probe file used to measure timestamp
resolution touch it. This ensures we always use the local system clock
when measuring filesystem timestamp resolution. This should prevent that
clock skew could influence the measured timestamp resolution in case of
a mounted network filesystem.

Bug: 548598
Change-Id: Iaeaf5967963f582395a195aa637b8188bfadac60
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-17 09:42:14 +02:00
Matthias Sohn 16760c3e9a Persist filesystem timestamp resolution and allow manual configuration
To enable persisting filesystem timestamp resolution per FileStore add a
new config section to the user global git configuration:

- Config section is "filesystem"
- Config subsection is concatenation of
  - Java vendor (system property "java.vm.vendor")
  - runtime version (system property "java.vm.version")
  - FileStore's name
  - separated by '|'
  e.g.
    "AdoptOpenJDK|1.8.0_212-b03|/dev/disk1s1"
  The prefix is needed since some Java versions do not expose the full
  timestamp resolution of the underlying filesystem. This may also
  depend on the underlying operating system hence concrete key values
  may not be portable.
- Config key for timestamp resolution is "timestampResolution" as a time
  value, supported time units are those supported by
  DefaultTypedConfigGetter#getTimeUnit

If timestamp resolution is already configured for a given FileStore
the configured value is used instead of measuring the resolution.

When timestamp resolution was measured it is persisted in the user
global git configuration.

Example:

[filesystem "AdoptOpenJDK|1.8.0_212-b03|/dev/disk1s1"]
	timestampResolution = 1 seconds

If locking the git config file fails retry saving the resolution up to 5
times in order to workaround races with another thread.

In order to avoid stack overflow use the fallback filesystem timestamp
resolution when loading FileBasedConfig which creates itself a
FileSnapshot to help checking if the config changed.

Note:
- on some OSes Java 8,9 truncate to milliseconds or seconds, see
https://bugs.openjdk.java.net/browse/JDK-8177809, fixed in Java 10
- UnixFileAttributes up to Java 12 truncates timestamp resolution to
microseconds when converting the internal representation to FileTime
exposed in the API, see https://bugs.openjdk.java.net/browse/JDK-8181493
- WindowsFileAttributes also provides only microsecond resolution up to
Java 12

Hence do not attempt to manually configure a higher timestamp resolution
than supported by the Java version being used at runtime.

Bug: 546891
Bug: 548188
Change-Id: Iff91b8f9e6e5e2295e1463f87c8e95edf4abbcf8
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-17 09:42:14 +02:00
Matthias Sohn 0966731cad Increase bazel timeout for long running tests
EolRepositoryTest and GcCommitSelectionTest timed out frequently when
running unit tests using bazel with the default timeout "moderate"
(300s). Increase timeout of these tests to "long" (900s).

Change-Id: I43588cf950f55b50f868d9fe9c66d22bd428a54c
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-16 12:11:22 +09:00
David Ostrovsky bbef67e8d0 Bazel: Fix lint warning flagged by buildifier
This change is fixing confusing name warning: [1].

  ./org.eclipse.jgit.test/tests.bzl:12: confusing-name:
  Never use 'l', 'I', or 'O' as names (they're too easily confused
  with 'I', 'l', or '0').

And is also fixing: "All calls to rules or macros should pass arguments
by keyword position argument" warning: [2].

  ./org.eclipse.jgit.test/BUILD:42: positional-args: All calls to rules
  or macros should pass arguments by keyword (arg_name=value) syntax.

[1] https://github.com/bazelbuild/buildtools/blob/master/WARNINGS.md#confusing-name
[2] https://github.com/bazelbuild/buildtools/blob/master/WARNINGS.md#positional-args

Change-Id: If5c28ec8a1ddc1d1b1035bd07b838a2a564aea4f
Signed-off-by: David Ostrovsky <david@ostrovsky.org>
2019-07-16 12:10:31 +09:00
David Ostrovsky 74da1b2701 Update bazlets to latest version
This is needed to make build tool chain compatible with the latest
Bazel releases.

Change-Id: I9822b5fe5f934457e6069217d687b3cf4764b7b7
Signed-off-by: David Ostrovsky <david@ostrovsky.org>
2019-07-16 12:10:31 +09:00
David Pursehouse 0aa8eca5f1 Bazel: Add missing dependencies for ArchiveCommandTest
Dependencies on commons-compress, xz, and jgit-archive are required
for the build to succeed.

Change-Id: I42f3721078a240ad93b8dcab909e66b9bfff0b56
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
2019-07-16 12:10:31 +09:00
David Pursehouse e54fde8616 Bazel: Remove FileTreeIteratorWithTimeControl from BUILD file
FileTreeIteratorWithTimeControl was deleted in a024759, but was
not removed from the BUILD file, thus causing the bazel build to
fail.

Change-Id: I892c0ffcac947298d0d6009374ee2c5d9afefb66
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
2019-07-16 11:20:21 +09:00
Matthias Sohn 121c957405 Add support for nanoseconds and microseconds for Config#getTimeUnit
Change-Id: I0a5828438810dd23790cba52d7ae2e055c6a3fc9
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-11 10:12:04 +02:00
Matthias Sohn a950eac23b Optionally measure filesystem timestamp resolution asynchronously
In order to avoid blocking on the main thread during measurement
interactive applications like EGit may want to measure the filesystem
timestamp resolution asynchronously.

In order to enable measurement in the background call
FileStoreAttributeCache.setAsyncfileStoreAttrCache(true)
before the first access to cached FileStore attributes.

Bug: 548188
Change-Id: I8c9a2dbfc3f1d33441edea18b90e36b1dc0156c7
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-11 10:12:04 +02:00
Matthias Sohn a024759cf5 Delete unused FileTreeIteratorWithTimeControl
The only usage of this test iterator was removed in df637928d. Hence
delete this iterator and associated test.

Change-Id: I47710133ec3edc675c21db210960c024982668c6
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-11 10:00:23 +02:00
Han-Wen Nienhuys 84e6c24e58 FileSnapshot#equals: consider UNKNOWN_SIZE
Add a unittest.

In commit I5485db55 ("Fix FileSnapshot's consideration of file size"),
the special casing of UNKNOWN_SIZE was forgotten.

This change, together with I493f3b57b ("Measure file timestamp
resolution used in FileSnapshot") introduced a regression that would
occasionally surface in Gerrit integration tests marked UseLocalDisk,
with the symptom that creating the Admin user in NoteDb failed with a
LOCK_FAILURE.

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Change-Id: I7ffd972581f815c144f810481103c7985af5feb0
2019-07-09 15:33:23 +02:00
Matthias Sohn 850b9d7540 Timeout measuring file timestamp resolution after 2 seconds
It was reported that measuring file timestamp resolution may hang
indefinitely on nfs. Hence timeout this measurement at the known worst
filesystem timestamp resolution (FAT) of 2 seconds.

Bug: 548188
Change-Id: I17004b0aa49d5b0e76360a008af3adb911b289c0
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2019-07-03 21:34:29 +02:00
Matthias Sohn 1159f9dd7c 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>
2019-07-03 21:34:27 +02:00
David Pursehouse dad9e1ff95 GlobalBundleCache: Fix ClassNewInstance warning from Error Prone
Error Prone reports:

  [ClassNewInstance] Class.newInstance() bypasses exception checking;
  prefer getDeclaredConstructor().newInstance()

  See https://errorprone.info/bugpattern/ClassNewInstance

This was the only occurrence of the warning in the code base; now it's
fixed, increase the severity to ERROR to prevent future occurrences.

Change-Id: Ic04d1c5d2bd458bbb4bb399d6ce9d147bd48d0b1
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
2019-06-22 18:44:23 +09:00
David Pursehouse 99a5fa2283 IncorrectObjectTypeException: Fix typos in constructors' Javadoc
Change-Id: Ib63310a603ba432e65d0c46e4b6b8d440ca6a115
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
2019-06-20 08:41:34 +09:00