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googlers / sop / jgit / c46c720e99baa081bff0dd7bcc1ae8ca48b5e3d1
commitc46c720e99baa081bff0dd7bcc1ae8ca48b5e3d1[log] [tgz]
authorTerry Parker <tparker@google.com>Thu May 18 01:30:14 2017 -0700
committerTerry Parker <tparker@google.com>Thu May 18 15:25:21 2017 -0700
tree13225554fd85d707bb2e361d820b580759535e88
parent69d5e89e99707119837eb1f025ee2c8d6d376996 [diff]
Exclude refs/tags from bitmap commit selection

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>
7 files changed
tree: 13225554fd85d707bb2e361d820b580759535e88
  1. .mvn/
  2. lib/
  3. org.eclipse.jgit/
  4. org.eclipse.jgit.ant/
  5. org.eclipse.jgit.ant.test/
  6. org.eclipse.jgit.archive/
  7. org.eclipse.jgit.http.apache/
  8. org.eclipse.jgit.http.server/
  9. org.eclipse.jgit.http.test/
  10. org.eclipse.jgit.junit/
  11. org.eclipse.jgit.junit.http/
  12. org.eclipse.jgit.lfs/
  13. org.eclipse.jgit.lfs.server/
  14. org.eclipse.jgit.lfs.server.test/
  15. org.eclipse.jgit.lfs.test/
  16. org.eclipse.jgit.packaging/
  17. org.eclipse.jgit.pgm/
  18. org.eclipse.jgit.pgm.test/
  19. org.eclipse.jgit.test/
  20. org.eclipse.jgit.ui/
  21. tools/
  22. .gitattributes
  23. .gitignore
  24. .mailmap
  25. BUILD
  26. CONTRIBUTING.md
  27. LICENSE
  28. pom.xml
  29. README.md
  30. WORKSPACE
README.md

Java Git

An implementation of the Git version control system in pure Java.

This package is licensed under the EDL (Eclipse Distribution License).

JGit can be imported straight into Eclipse, built and tested from there, but the automated builds use Maven.

  • org.eclipse.jgit

    A pure Java library capable of being run standalone, with no additional support libraries. It provides classes to read and write a Git repository and operate on a working directory.

    All portions of JGit are covered by the EDL. Absolutely no GPL, LGPL or EPL contributions are accepted within this package.

  • org.eclipse.jgit.ant

    Ant tasks based on JGit.

  • org.eclipse.jgit.archive

    Support for exporting to various archive formats (zip etc).

  • org.eclipse.jgit.http.apache

    Apache httpclient support

  • org.eclipse.jgit.http.server

    Server for the smart and dumb Git HTTP protocol.

  • org.eclipse.jgit.pgm

    Command-line interface Git commands implemented using JGit (“pgm” stands for program).

  • org.eclipse.jgit.packaging

    Production of Eclipse features and p2 repository for JGit. See the JGit Wiki on why and how to use this module.

Tests

  • org.eclipse.jgit.junit

    Helpers for unit testing

  • org.eclipse.jgit.test

    Unit tests for org.eclipse.jgit

  • org.eclipse.jgit.ant.test

  • org.eclipse.jgit.pgm.test

  • org.eclipse.jgit.http.test

  • org.eclipse.jgit.junit.test

    No further description needed

Warnings/Caveats

  • Native smbolic links are supported, provided the file system supports them. For Windows you must have Windows Vista/Windows 2008 or newer, use a non-administrator account and have the SeCreateSymbolicLinkPrivilege.

  • Only the timestamp of the index is used by jgit if the index is dirty.

  • JGit requires at least a Java 8 JDK.

  • CRLF conversion is performed depending on the core.autocrlf setting, however Git for Windows by default stores that setting during installation in the “system wide” configuration file. If Git is not installed, use the global or repository configuration for the core.autocrlf setting.

  • The system wide configuration file is located relative to where C Git is installed. Make sure Git can be found via the PATH environment variable. When installing Git for Windows check the “Run Git from the Windows Command Prompt” option. There are other options like Eclipse settings that can be used for pointing out where C Git is installed. Modifying PATH is the recommended option if C Git is installed.

  • We try to use the same notation of $HOME as C Git does. On Windows this is often not the same value as the user.home system property.

Package Features

  • org.eclipse.jgit/

    • Read loose and packed commits, trees, blobs, including deltafied objects.

    • Read objects from shared repositories

    • Write loose commits, trees, blobs.

    • Write blobs from local files or Java InputStreams.

    • Read blobs as Java InputStreams.

    • Copy trees to local directory, or local directory to a tree.

    • Lazily loads objects as necessary.

    • Read and write .git/config files.

    • Create a new repository.

    • Read and write refs, including walking through symrefs.

    • Read, update and write the Git index.

    • Checkout in dirty working directory if trivial.

    • Walk the history from a given set of commits looking for commits introducing changes in files under a specified path.

    • Object transport Fetch via ssh, git, http, Amazon S3 and bundles. Push via ssh, git and Amazon S3. JGit does not yet deltify the pushed packs so they may be a lot larger than C Git packs.

    • Garbage collection

    • Merge

    • Rebase

    • And much more

  • org.eclipse.jgit.pgm/

    • Assorted set of command line utilities. Mostly for ad-hoc testing of jgit log, glog, fetch etc.

  • org.eclipse.jgit.ant/

    • Ant tasks

  • org.eclipse.jgit.archive/

    • Support for Zip/Tar and other formats

  • org.eclipse.http.*/

    • HTTP client and server support

Missing Features

There are some missing features:

  • gitattributes support

Support

Post question, comments or patches to the jgit-dev@eclipse.org mailing list. You need to be subscribed to post, see here:

https://dev.eclipse.org/mailman/listinfo/jgit-dev

Contributing

See the EGit Contributor Guide:

http://wiki.eclipse.org/EGit/Contributor_Guide

About Git

More information about Git, its repository format, and the canonical C based implementation can be obtained from the Git website:

http://git-scm.com/