* stable-5.9:
Prevent infinite loop rescanning the pack list on
PackMismatchException
Remove blank in maven.config
Change-Id: I15ff2d7716ecaceb0eb87b8823d85670f5db709d
We found, when analysing an incident where Gerrit's gc runner thread got
stuck, that we can end up in an infinite loop in
ObjectDirectory#openPackedObject which tries to rescan the pack
list and starts over trying to open a packed object in an unconfined
loop if it catches a PackMismatchException.
Here the relevant part of a thread dump we created while the gc runner
was stuck:
"WorkQueue-2[java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask@350812a3[Not
completed,
task = java.util.concurrent.Executors$RunnableAdapter@5425d7ee]]" #72
tid=0x00007f73cee1c800 nid=0x584
runnable [0x00007f7392d57000]
java.lang.Thread.State: RUNNABLE
at org.eclipse.jgit.internal.storage.file.WindowCache.removeAll(WindowCache.java:716)
at org.eclipse.jgit.internal.storage.file.WindowCache.purge(WindowCache.java:399)
at org.eclipse.jgit.internal.storage.file.PackFile.close(PackFile.java:296)
at org.eclipse.jgit.internal.storage.file.ObjectDirectory.reuseMap(ObjectDirectory.java:973)
at org.eclipse.jgit.internal.storage.file.ObjectDirectory.scanPacksImpl(ObjectDirectory.java:904)
at org.eclipse.jgit.internal.storage.file.ObjectDirectory.scanPacks(ObjectDirectory.java:895)
- locked <0x000000050a498f60> (a
java.util.concurrent.atomic.AtomicReference)
at org.eclipse.jgit.internal.storage.file.ObjectDirectory.searchPacksAgain(ObjectDirectory.java:794)
at org.eclipse.jgit.internal.storage.file.ObjectDirectory.openPackedObject(ObjectDirectory.java:465)
at org.eclipse.jgit.internal.storage.file.ObjectDirectory.openPackedFromSelfOrAlternate(ObjectDirectory.java:417)
at org.eclipse.jgit.internal.storage.file.ObjectDirectory.openObject(ObjectDirectory.java:408)
at org.eclipse.jgit.internal.storage.file.WindowCursor.open(WindowCursor.java:132)
at org.eclipse.jgit.lib.ObjectReader$1.open(ObjectReader.java:279)
at org.eclipse.jgit.revwalk.RevWalk$2.next(RevWalk.java:1031)
at org.eclipse.jgit.internal.storage.pack.PackWriter.findObjectsToPack(PackWriter.java:1911)
at org.eclipse.jgit.internal.storage.pack.PackWriter.preparePack(PackWriter.java:960)
at org.eclipse.jgit.internal.storage.pack.PackWriter.preparePack(PackWriter.java:876)
at org.eclipse.jgit.internal.storage.file.GC.writePack(GC.java:1168)
at org.eclipse.jgit.internal.storage.file.GC.repack(GC.java:852)
at org.eclipse.jgit.internal.storage.file.GC.doGc(GC.java:269)
at org.eclipse.jgit.internal.storage.file.GC.gc(GC.java:220)
at org.eclipse.jgit.api.GarbageCollectCommand.call(GarbageCollectCommand.java:179)
at com.google.gerrit.server.git.GarbageCollection.run(GarbageCollection.java:112)
at com.google.gerrit.server.git.GarbageCollection.run(GarbageCollection.java:75)
at com.google.gerrit.server.git.GarbageCollection.run(GarbageCollection.java:71)
at com.google.gerrit.server.git.GarbageCollectionRunner.run(GarbageCollectionRunner.java:76)
at com.google.gerrit.server.logging.LoggingContextAwareRunnable.run(LoggingContextAwareRunnable.java:103)
at java.util.concurrent.Executors$RunnableAdapter.call(java.base@11.0.18/Executors.java:515)
at java.util.concurrent.FutureTask.runAndReset(java.base@11.0.18/FutureTask.java:305)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(java.base@11.0.18/ScheduledThreadPoolExecutor.java:305)
at com.google.gerrit.server.git.WorkQueue$Task.run(WorkQueue.java:612)
at java.util.concurrent.ThreadPoolExecutor.runWorker(java.base@11.0.18/ThreadPoolExecutor.java:1128)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(java.base@11.0.18/ThreadPoolExecutor.java:628)
at java.lang.Thread.run(java.base@11.0.18/Thread.java:829)
The code in ObjectDirectory#openPackedObject [1] apparently assumes that
this is caused by a transient problem which it can resume from by
retrying. We use `core.trustFolderStat = false` on this server since it
uses NFS. The incident we had showed that we can enter into an infinite
loop here if there is a permanent mismatch between a pack file and its
corresponding pack index. I am not yet sure how this can happen.
Break the infinite loop by limiting the number of attempts rescanning
the pack list to 5 retries. When we exceed this threshold set the type
of the PackMismatchException to permanent and rethrow it which breaks
the infinite loop.
Also apply the same limit in #getPackedObjectSize
and #selectObjectRepresentation where we use similar retry loops.
[1] 011c26ff36/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/ObjectDirectory.java (465)
Change-Id: I20fb63bcc1fdc3a03d39b963f06a90e6f0ba73dc
SmartHttpPushConnection: close InputStream and OutputStream after
processing. Wrap IOExceptions which aren't TransportExceptions already
as a TransportException.
Also-By: Matthias Sohn <matthias.sohn@sap.com>
Change-Id: I8e11d899672fc470c390a455dc86367e92ef9076
FileBasedConfig should not rely on auto-detection of
the file-snapshot attribute computation based on config.
The check was already performed when a new FileBasedConfig
is created at L158:
// don't use config in this snapshot to avoid endless recursion
newSnapshot = FileSnapshot.saveNoConfig(getFile());
The check was missing though when the FileBasedConfig is saved
to disk and the new snapshot is obtained from the associated
LockFile.
This change fixes the issue by keeping a non-config based
FileSnapshot also after a FileBasedConfig is saved.
Bug: 577983
Change-Id: Id1e410ba687e683ff2b2643af31e1110b103b356
* stable-5.9:
Revert "RefDirectory.scanRef: Re-use file existence check done in snapshot creation"
Change-Id: I2a84c838a886d1d6383c34f50b418baa743c57b0
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
* stable-5.8:
Revert "RefDirectory.scanRef: Re-use file existence check done in snapshot creation"
Change-Id: I88a629e571fec5a9820114ebf5765b5d94a276bd
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
* stable-5.7:
Revert "RefDirectory.scanRef: Re-use file existence check done in snapshot creation"
Change-Id: Ied786ab5e3c0dd05f701705fce2d4ad85502c4d6
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
* stable-5.6:
Revert "RefDirectory.scanRef: Re-use file existence check done in snapshot creation"
Change-Id: I454622dae6eb95aedbd858e3b12da72282d36673
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
* stable-5.5:
Revert "RefDirectory.scanRef: Re-use file existence check done in snapshot creation"
Change-Id: I2622f1d384a88a556ba9d88f0d08a37af69e530c
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
* stable-5.4:
Revert "RefDirectory.scanRef: Re-use file existence check done in snapshot creation"
Change-Id: Ia1665dd92ccc3811a6116f41421a05aca10fc6eb
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
* stable-5.3:
Revert "RefDirectory.scanRef: Re-use file existence check done in snapshot creation"
Change-Id: I52a57a17abe60e30e3d7615f8cb4d0c5e6aebd9b
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
* stable-5.2:
Revert "RefDirectory.scanRef: Re-use file existence check done in snapshot creation"
Change-Id: Id37f47a5ef2e3c8329eca30c171941f7e5606a85
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
* stable-5.1:
Revert "RefDirectory.scanRef: Re-use file existence check done in snapshot creation"
Change-Id: I625667c2718ab31ae7df907c3dd6024a933913b8
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
This reverts commit f829f5f838.
Using MISSING_FILEKEY as indicator for a non-existing file doesn't work
on Windows.
Bug: 577954
Change-Id: I92102a3d259f6cc0f367096a3213cfa794466817
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
Return immediately in scanRef if the loose ref was identified as
missing when a snapshot was attempted for the ref. This will help
performance of scanRef when the ref is packed but has a corresponding
empty dir in 'refs/'.
For example, consider the case where we create 50k sharded refs in
a new namespace called 'new-refs' using an atomic 'BatchRefUpdate'.
The refs are named like 'refs/new-refs/01/1/1', 'refs/new-refs/01/1/2',
'refs/new-refs/01/1/3' and so on. After the refs are created, the
'new-refs' namespace looks like below:
$ find refs/new-refs -type f | wc -l
0
$ find refs/new-refs -type d | wc -l
5101
At this point, an 'exactRef' call on each of the 50k refs without
this change takes ~2.5s, where as with this change it takes ~1.5s.
Change-Id: I926bc41b9ae89a1a792b1b5ec9a17b05271c906b
Signed-off-by: Kaushik Lingarkar <quic_kaushikl@quicinc.com>
Doing a getFileStoreAttributes call even when the file doesn't
exist is unnecessary. This call is particularly slow on some
filesystems. Instead, do it only when the file exists and load
the appropriate cache.
This update can help speed up RefDirectory.exactRef when the ref
is packed, but has a corresponding empty dir for it under 'refs/'.
This scenario can happen when an atomic 'BatchRefUpdate' creates
new sharded refs.
For example, consider the case where we create 50k sharded refs in
a new namespace called 'new-refs' using an atomic 'BatchRefUpdate'.
The refs are named like 'refs/new-refs/01/1/1', 'refs/new-refs/01/1/2',
'refs/new-refs/01/1/3' and so on. After the refs are created, the
'new-refs' namespace looks like below:
$ find refs/new-refs -type f | wc -l
0
$ find refs/new-refs -type d | wc -l
5101
At this point, an 'exactRef' call on each of the 50k refs without
this change takes ~30s, where as with this change it takes ~2.5s.
Change-Id: I4a5d4c6a652dbeed1f4bc3b4f2b2f1416f7ca0e7
Signed-off-by: Kaushik Lingarkar <quic_kaushikl@quicinc.com>
The command 'git config --system --show-origin --list -z' fails if
the system config doesn't exist. Use debug logging instead of a
warning for failures of that command. Typically the user cannot do
anything about it anyway, and JGit will just work without system
config.
Bug: 577492
Change-Id: If628ab376182183aea57a385c169e144d371bbb2
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
* stable-5.9:
Better git system config finding
Change-Id: I1022d003e0d3b9d452abfed9ac49663d0a93c6e6
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
We've used "GIT_EDITOR=edit git config --system --edit" to determine
the location of the git system config for a long time. But git 2.34.0
always expects this command to have a tty, but there isn't one when
called from Java. If there isn't one, the Java process may get a
SIGTTOU from the child process and hangs.
Arguably it's a bug in C git 2.34.0 to unconditionally assume there
was a tty. But JGit needs a fix *now*, otherwise any application using
JGit will lock up if git 2.34.0 is installed on the machine.
Therefore, use a different approach if the C git found is 2.8.0 or
newer: parse the output of
git config --system --show-origin --list -z
"--show-origin" exists since git 2.8.0; it prefixes the values with
the file name of the config file they come from, which is the system
config file for this command. (This works even if the first item in
the system config is an include.)
Bug: 577358
Change-Id: I3ef170ed3f488f63c3501468303119319b03575d
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
(cherry picked from commit 9446e62733)
* stable-5.9:
Fix missing peel-part in lsRefsV2 for loose annotated tags
reftable: drop code for truncated reads
reftable: pass on invalid object ID in conversion
Update eclipse-jarsigner-plugin to 1.3.2
Fix running benchmarks from bazel
Update eclipse-jarsigner-plugin to 1.3.2
Change-Id: I4e7c7727ebfa9a7748477f2300bd66d775548ad6
We observed the following issue:
$ git tag -a v1.0 -m v1.0
$ git push origin tag v1.0
$ git ls-remote origin v1.0^{}
... empty result ...
On the server (Gerrit) side run git-gc to pack the refs:
$ git gc
Repeat the ls-remote from the client and the result is correct:
$ git ls-remote origin v1.0^{}
7ad85c810de3ae922903d4bdd17c53cd627260ba refs/tags/v1.0^{}
Unfortunately, the existing UploadPackTest didn't reveal this issue
although it provided the test case needed to do so: testV2LsRefsPeel.
This is because The UploadPackTest uses InMemoryRepository which
internally uses Dfs* implementations. The issue is only reproducible
when using the FileRepository.
It is a non-trivial task to refactor the UploadPackTest to work against
both InMemoryRepository and FileRepository and this change is not trying
to do that. This change creates a new test:
UploadPackLsRefsFileRepositoryTest and copies the necesssary code from
the UploadPackTest.
Change-Id: Icfc7d0ca63f1524bafe24c9626ce12ea72aa3718
Signed-off-by: Saša Živkov <sasa.zivkov@sap.com>
* stable-5.8:
reftable: drop code for truncated reads
reftable: pass on invalid object ID in conversion
Update eclipse-jarsigner-plugin to 1.3.2
Change-Id: I9e66ef90dc9a65bac47b35705d679bf992bd72b9
* stable-5.7:
reftable: drop code for truncated reads
reftable: pass on invalid object ID in conversion
Update eclipse-jarsigner-plugin to 1.3.2
Change-Id: I88c47ff57f4829baec5b19aad3d8d6bd21f31a86
* stable-5.6:
reftable: drop code for truncated reads
reftable: pass on invalid object ID in conversion
Update eclipse-jarsigner-plugin to 1.3.2
Change-Id: I1c18f5f435f4a4a86e0548a310dbfc74191e1ed5
The reftable format is a block based format, but allows for variably
sized blocks. This obviously happens for reflog blocks (which are zlib
compressed), but is also accepted for index blocks: In the spec, this
is motivated as
To achieve constant O(1) disk seeks for lookups the index must be
a single level, which is permitted to exceed the file's
configured block size, but not the format's max block size of
15.99 MiB.
Hence, when parsing a block, one cannot be sure of its exact size:
after reading a default-size block (eg. 4kb), the block header may
state that the block is in fact larger.
Before, the code would mark the block as `truncated`, noting
// Its OK during sequential scan for an index block to have been
// partially read and be truncated in-memory. This happens when
// the index block is larger than the file's blockSize. Caller
// will break out of its scan loop once it sees the blockType.
This looks like either
* a remnant of never-implemented functionality. There is no reason to
ever sequentially scan an index block.
* alluding to sequential scan of the data blocks before the index
blocks (eg. scanning refs, which ends when we find the first ref index
block, and we can then ignore the index block).
This comment is followed by code that populates the
restartTbl/restartCnt fields relative to the (possibly truncated)
buffer. If the buffer is truncated, this essentially reads garbage,
leading to OOB array access when using the index block.
Fix this by dropping the truncated logic and issuing a second read if
the first read was short.
Add a test.
We have never observed this failure scenario at Google. We use 64kb
blocksize, which requires us to need fewer index entries. The reftable
spec mentions an Android repo of size 36M. With 64kb blocks, that's
just 562 index entries. Even with historical growth, we are long from
requiring an index whose size exceeds a single block.
When adding the analogous test for seeking refs, there was no failure.
This points to another possibility which is that the code tries to
avoid writing large index blocks for refs.
I did not investigate further which one it is.
Fixes https://bugs.eclipse.org/bugs/show_bug.cgi?id=576250
Bug: 576250
Change-Id: I41ec21fac9e526ef57b3d6fb57b988bd353ee338
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Before, while trying to determine if an object ID was a tag or not,
the reftable conversion would yield an exception.
Change-Id: I3688a0ffa9e774ba27f320e3840ff8cada21ecf0
When reading loose objects over NFS it is possible that the OS syscall
would fail with ESTALE errors: This happens when the open file
descriptor no longer refers to a valid file.
Notoriously it is possible to hit this scenario when git data is shared
among multiple clients, for example by multiple gerrit instances in HA.
If one of the two clients performs a GC operation that would cause the
packing and then the pruning of loose objects, the other client might
still hold a reference to those objects, which would cause an exception
to bubble up the stack.
The Linux NFS FAQ[1] (at point A.10), suggests that the proper way to
handle such ESTALE scenarios is to:
"[...] close the file or directory where the error occurred, and reopen
it so the NFS client can resolve the pathname again and retrieve the new
file handle."
In case of a stale file handle exception, we now attempt to read the
loose object again (up to 5 times), until we either succeed or encounter
a FileNotFoundException, in which case the search can continue to
Packfiles and alternates.
The limit of 5 provides an arbitrary upper bounds that is consistent to
the one chosen when handling stale file handles for packed-refs
files (see [2] for context).
[1] http://nfs.sourceforge.net/
[2] https://git.eclipse.org/r/c/jgit/jgit/+/54350
Bug: 573791
Change-Id: I9950002f772bbd8afeb9c6108391923be9d0ef51
Matthias Sohn