Reorder modifiers to follow Java Language Specification
The Java Language Specification recommends listing modifiers in
the following order:
1. Annotations
2. public
3. protected
4. private
5. abstract
6. static
7. final
8. transient
9. volatile
10. synchronized
11. native
12. strictfp
Not following this convention has no technical impact, but will reduce
the code's readability because most developers are used to the standard
order.
This was detected using SonarLint.
Change-Id: I9cddecb4f4234dae1021b677e915be23d349a380
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
RevWalk: stop mixing lines of history in topo sort
The topological sort algorithm in TopoSortGenerator for RevWalk may mix
multiple lines of history, producing results that differ from C git's
git log whose man page states: "Show no parents before all of its
children are shown, and avoid showing commits on multiple lines of
history intermixed." Lines of history are mixed because
TopoSortGenerator merely delays a commit until all of its children have
been produced; it does not immediately produce a commit after its last
child has been produced.
Therefore, when the last child of a commit has been produced, unpop the
commit so that it will be returned upon the subsequent call to next() in
TopoSortGenerator. To avoid producing duplicates, mark commits that
have not yet been produced as TOPO_QUEUED so that when a commit is
popped, it is produced if and only if TOPO_QUEUED is set.
To support nesting with other generators that may produce the same
commit multiple times like DepthGenerator (for example, StartGenerator
does this), do not increment parent inDegree for the same child commit
more than once.
Modify tests that assert that TopoSortGenerator mixes lines of commit
history.
Change-Id: I4ee03c7a8e5265d61230b2a01ae3858745b2432b
Signed-off-by: Alex Spradlin <alexaspradlin@google.com>
The ReftableCompactor supported a byteLimit, but this is currently
unused. The FileReftableStack has a more sophisticated strategy that
amortizes compaction costs.
Rename min/maxUpdateIndex to reflogExpire{Min,Max}UpdateIndex to
reflect their purpose more accurately.
Since reflogs are generally pruned chronologically (oldest entries are
expired first), one can only prune entries on full compaction, so they
should not be set by default.
Rephrase the function Reader#minUpdateIndex and maxUpdateIndex. These
vars are documented to affect log entries, but semantically, they are
about ref entries. Since ref entries have their timestamps
delta-compressed, it is important for the min/maxUpdateIndex values to
be coherent between different tables.
The logical timestamps for log entries do not have to be coherent in
different tables, as the timestamps of a log entry is part of the key.
For example, a table written at update index 20 may contain a tombstone
log entry at timestamp 1.
Therefore, we set ReftableWriter's min/maxUpdateIndex from the merged
tables we are compacting, rather than from the compaction settings
(which should only control reflog expiry.)
The previous behavior could drop log entries erroneously, especially
in the presence of tombstone log entries. Unfortunately, testing this
properly requires both an API for adding log tombstones, and a more
refined API for controlling automatic compaction. Hence, no test.
Change-Id: I2f4eb7866f607fddd0629809e8e61f0b9097717f
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
The merged table contains handles to open files. A full compaction
causes those files to be closed, and so further lookups would fail
with EBADF.
Change-Id: I7bb74f7228ecc7fec9535b00e56a617a9c18e00e
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Commit 6216b0de changed the behavior of the setMirror(),
setCloneAllBranches(), and setBranchesToClone() operations. Before
that commit, these could be set and reset independently and only in
call() it would be determined what exactly to do. Since that commit,
the last of these calls would determine the operation. This means
that the sequence
cloneCommand.setCloneAllBranches(true);
cloneCommand.setBranchesToClone(/* some list of refs */);
would formerly do a "clone all" giving a fetch refspec with wildcards
+refs/heads/*:refs/remotes/origin/*
which picks up new upstream branches, whereas since commit 6216b0de
individual non-wildcard fetch refspecs would be generated and new
upstream branches would not be fetched anymore.
Undo this behavioral change. Make the operations independently settable
and resettable again, and determine the exact operation only in call():
mirror=true > cloneAll=true > specific refs, where ">" means "takes
precedence over", and if none is set assume cloneAll=true.
Note that mirror=true implies setBare(true).
Bug: 559796
Change-Id: I7162b60e99de5e3e512bf27ff4113f554c94f5a6
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
FS: Don't use innocuous threads for CompletableFuture
The default threads from the ForkJoinPool run without any privileges
when a SecurityManager is installed, leading to SecurityExceptions
when trying to create the probe file even if the application otherwise
has write privileges in the directory.
Use a dedicated ThreadPoolExecutor using daemon threads instead.
Bug: 551690
Change-Id: Id5376f09f0d7da5ceea367e1f0dfc70f823d62d3
Signed-off-by: Alex Jitianu <alex_jitianu@sync.ro>
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
Enable UnusedException at ERROR level which causes the build to fail
in many places with:
[UnusedException] This catch block catches an symbol and re-throws
another, but swallows the caught symbol rather than setting it as a
cause. This can make debugging harder.
Fix it by setting the caught exception as cause on the subsequently
thrown exception.
Note: The grammatically incorrect error message is copy-pasted as-is
from the version of ErrorProne currently used in Bazel; it has been
fixed by [1] in the latest version.
[1] https://github.com/google/error-prone/commit/d57a39c
Change-Id: I11ed38243091fc12f64f1b2db404ba3f1d2e98b5
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Since version 4.13 JUnit has an assertThrows method. Remove the
implementation in MoreAsserts and use the one from JUnit.
CQ: 21439
Change-Id: I086baa94aa3069cebe87c4cbf91ed1534523c6cb
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
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>
and switch over strings where possible. Sometimes if statements are
chained and form a series of comparisons against constants. Using switch
statements improves readability.
Bug: 545856
Change-Id: Iacb78956ee5c20db4d793e6b668508ec67466606
Signed-off-by: Carsten Hammer <carsten.hammer@t-online.de>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
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>
- if a test can throw different exceptions declare it throws Exception
- fix code formatting
Change-Id: I55d63918f3163b31f2297d6217d5855108dd43b5
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
CLI: Add support for excluding paths from Git log command
Git log supports the exclude pathspec, which allows for excluding paths
from the log command. JGit only supports adding paths to the log
command. See the following StackOverflow question for details:
https://stackoverflow.com/questions/59143934/java-jgit-how-to-get-git-
commits-not-affecting-certain-directories
This commit adds an excludePath() method to the log command. It does not
yet support regex or glob wildcards.
Change-Id: I8cd59950b87850b55a15c7e2ea5470145c9aae28
Signed-off-by: John Tipper <john_tipper@hotmail.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
ReftableTest: Clean up boxing warnings on usage of String.format
Passing int as an argument to String.format causes a warning:
The expression of type int is boxed into Integer
Most of these are already suppressed, but there are a couple that are
not. Add suppressions for those.
For the existing ones, move the suppression scope from the method to
the actual usage. Where necessary extract the usage out to a local
variable.
Change-Id: I7a7ff6dec49467e4b5c58d27a231c74e6e1c5437
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
The reftable format supports fast inverse (SHA1 => ref) queries.
If the ref database does not support fast inverse queries, it may be
advantageous to build a complete SHA1 to ref map in advance for
multiple uses. To let applications decide, this function indicates
whether the inverse map is available.
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Change-Id: Idaf7e01075906972ec21332cade285289619c2b3
This removes a raw IOException at one level. Later we'll add a custom
exception handling mechanism like UploadPack.
Change-Id: I52a7423798c97b032d848351be8b6f144776b017
Signed-off-by: Masaya Suzuki <masayasuzuki@google.com>
When a conflicting file was blamed, JGit would not identify lines
coming from the merge parents. The main cause for this was that
Blame and BlameCommand simply added the first DirCacheEntry found
for a file to its queue of candidates (blobs or commits) to consider.
In case of a conflict this typically is the merge base commit, and
comparing a auto-merged contents against that base would yield
incorrect results.
Such cases have to be handled specially. The candidate to be
considered by the blame must use the working tree contents, but
at the same time behave like a merge commit/candidate with HEAD
and the MERGE_HEADs as parents. Canonical git does something very
similar, see [1].
Implement that and add tests.
I first did this for the JGit pgm Blame command. When I then tried
to do the same in BlameCommand, I noticed that the latter also
included some fancy but incomplete CR-LF handling. In order to
be able to use the new BlameGenerator.prepareHead() also in
BlameCommand this CR-LF handling was also moved into BlameGenerator
and corrected in doing so.
(Just considering the git config settings was not good enough,
CR-LF behavior can also be influenced by .gitattributes, and even
by whether the file in the index has CR-LF. To correctly determine
CR-LF handling for check-in one needs to do a TreeWalk with at
least a FileTreeIterator and a DirCacheIterator.)
[1] https://github.com/git/git/blob/v2.22.0/blame.c#L174
Bug: 434330
Change-Id: I9d763dd6ba478b0b6ebf9456049d6301f478ef7c
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
Add missing license header to UploadPackRefSortingForReachabilityTest
Forgot to add this in commit 989a927a5f
(checkNotAdvertisedWants: Be lazy convering Ref to RevCommit,
2019-11-20).
Change-Id: I5c1177ac60eabb3a71959bbad4537e076a901b7e
Signed-off-by: Jonathan Nieder <jrn@google.com>
RepositoryCache: don't require HEAD in git repositories
Reftable-enabled repositories don't have a file called HEAD. Check for
reftable/ instead.
This fixes repository creation on reftable in Gerrit.
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Change-Id: I778c2be01d96aaf135affae4b457b5fe5b483bee
BitmappedReachabilityChecker: Use only one bitmap for the whole check
The checker is creating a new bitmap per branch leading to excessive
memory consumption. For the reachability check one bitmap with the
reachability of all branches aggregated is enough.
Build the reachability bitmap with a filter. The filter itself uses it
to emit only commits not reached before and the caller to check what
targets have been reached already.
BitmapCalculator is not required anymore.
Change-Id: Ic5c62f77fe0f188913215b7eaa51d849a9aae6a5
Signed-off-by: Ivan Frade <ifrade@google.com>
checkNotAdvertisedWants: Be lazy converting Ref to RevCommit
The ref points to an ObjectId that then is translated into a RevCommit.
This translation can be costly and with the incremental reachability
check is probably not needed for most of the elements.
Delay the translation from ObjectId to RevCommit to when it is needed.
Use Streams, that have the laziness built-in, all the way from Ref to
RevCommit.
This should reduce the latency for reachability checks over big sets of
references.
Change-Id: I28693087321b2beff3eaa1f3d2e7840ab0eedc6d
Signed-off-by: Ivan Frade <ifrade@google.com>
ReachabilityChecker: Receive a Stream instead of a Collection
Preparatory change. Converting ObjectIds to RevCommits is potentially
expensive and in the incremental reachability check, it is probably not
required for all elements in the collection.
Pass a Stream to the reachability checker. In the follow up we make
the conversion from ObjectId to RevCommit in the stream (i.e. on
demand). This should reduce the latency of reachability checks over big
sets of references.
Change-Id: I9f310e331de5b0bf8de34143bd7dcd34316d2fba
Signed-off-by: Ivan Frade <ifrade@google.com>
Reftable is a binary, block-based storage format for the ref-database.
It provides several advantages over the traditional packed + loose
storage format:
* O(1) write performance, even for deletions and transactions.
* atomic updates to the ref database.
* O(log N) lookup and prefix scans
* free from restrictions imposed by the file system: it is
case-sensitive even on case-insensitive file systems, and has
no inherent limitations for directory/file conflicts
* prefix compression reduces space usage for repetitive ref names,
such as gerrit's refs/changes/xx/xxxxx format.
FileReftableDatabase is based on FileReftableStack, which does
compactions inline. This is simple, and has good median performance,
but every so often it will rewrite the entire ref database.
For testing, a FileReftableTest (mirroring RefUpdateTest) is added to
check for Reftable specific behavior. This must be done separately, as
reflogs have different semantics.
Add a reftable flavor of BatchRefUpdateTest.
Add a FileReftableStackTest to exercise compaction.
Add FileRepository#convertToReftable so existing testdata can be
reused.
CQ: 21007
Change-Id: I1837f268e91c6b446cb0155061727dbaccb714b8
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Prevent adding a null parent to a commit's parent array. Doing so
can cause NPEs later on.
Bug: 552160
Change-Id: Ib24b7b9b7b08e0b6f246006b4a4cade7eeb830b9
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
Michael Dardis
David Pursehouse
Alex Spradlin
Andrey Loskutov
Matthias Sohn
Han-Wen Nienhuys
Thomas Wolf
Alex Jitianu
Carsten Hammer
John Tipper
Masaya Suzuki
Jonathan Nieder
Ivan Frade