Difference between revisions of "Git"

Revision as of 11:46, 4 May 2007

Git is a popular version control system designed to handle very large projects with speed and efficiency. See http://git.or.cz/ for more info.

The Windows users might be interested in the MinGW git port (binaries).

Git and OpenOffice.org

A functional git tree with the entire OOo history for testing purposes is here: http://go-oo.org/git. It is an imported CVS tree that was split into two parts:

• The sources themselves - ooo.git
• The 3rd party stuff (binary mozilla, zlib, berkeleydb, ...) - 3rdparty.git

The size of the sources is about 1.3G, the size of the 3rd party stuff is 591M. Please follow the instructions on http://go-oo.org/git to get the tree.

Transformations

These transformations are done while converting from CVS:

• The OOo repository is split into the sources and 3rd party sources as described above
• 'cws_src680_xyz' branches are renamed to simple 'xyz'
• 'CWS_SRC680_XYZ_ANCHOR' tags are renamed to simple 'XYZ'
• 'INTEGRATION: CWS xyz' commits are grouped into one commit (they are generated by CWS tooling per-file), and treated as a merge in the git tree
• Tabs are converted to 4 spaces at the beginning of the lines in .c/.cxx/.h/.hxx/.mk/.src
• 'RESYNC:.*FILE MERGED', and 'RESYNC:.*FILE REMOVED' are grouped inside branches (with single 'RESYNC' log entry)
  • May result in multiple 'RESYNC' commits inside the branch when a commit happened to another one in the middle of the resync

Requirements/TODO

• Convert CollabNet account names into real names
  • maybe use the data from DomainDeveloper (complete that where necessary) if there's no easy way to extract the names from CollabNet
• Delete merged branches (from 'heads', not from history!)
• Provide the too old history as 'graft' - see eg. http://repo.or.cz/w/elinks.git?a=blob;f=contrib/grafthistory.sh
• Translations to a separate git tree as well?
• URE to a separate git tree?
• ODF Toolkit to a separate git tree?
• .pdf version of developer's guide consume quite some space as well - any chance to do something with it?

Comparison

General

Links to Git comparison with other SCMs: http://git.or.cz/gitwiki/GitLinks#comparison

Comparison of git with Subversion: http://git.or.cz/gitwiki/GitSvnComparsion

Machines used for the testing

CVS tests:

•  ???

Git tests:

• CPU: AMD Athlon(tm) 64 Processor 3200+
• RAM: 1G
• Disk (info from bonnie):

              ---Sequential Output (nosync)--- ---Sequential Input-- --Rnd Seek-
              -Per Char- --Block--- -Rewrite-- -Per Char- --Block--- --04k (03)-
Machine    MB K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU   /sec %CPU
one    1*2000 37819 77.6 44296 16.8 16982  5.1 35203 63.9 45915  6.6  152.4  0.4

• OS: SUSE 10.1

SVN tests:

•  ???

Notes

The git repository could [should! ;-)] be tuned for better results:

• Delete integrated branches - the history will be still preserved, just the number of open heads will reduce (by about 3000)
• Graft history - the old development can be 'hidden' and available just to those who really need it using a simple script, like http://repo.or.cz/w/elinks.git?a=blob;f=contrib/grafthistory.sh . This way we can save about 1G of download!

The Results

'3rd party' in this context means the following modules: agg, beanshell, berkeleydb, bitstream_vera_fonts, boost, curl, dictionaries, epm, expat, freetype, hsqldb, icu, jpeg, libwpd, libxml2, moz, msfontextract, nas, neon, np_sdk, portaudio, python, sablot, sane, sndfile, stlport, vigra, xalan, xt, zlib.

Commands used for the tests: