bdiff: improve worst case behavior by 100x.
on 5.8MB (244.000 lines) text file with similar lines, hash before
this change made diff against empty file take 75 seconds. this change
improves performance to 0.6 seconds. result is that clone of smallish
repo (137MB) with some files like this takes 1 minute instead of 10
minutes.
common case of diff is 10% slower now, probably because of worse cache
locality. but diff does not affect overall performance in common case
(less than 1% of runtime is in diff when it is working ok), so this
tradeoff looks good.
MERCURIAL QUICK-START
Setting up Mercurial:
Note: some distributions fails to include bits of distutils by
default, you'll need python-dev to install. You'll also need a C
compiler and a 3-way merge tool like merge, tkdiff, or kdiff3.
First, unpack the source:
$ tar xvzf mercurial-<ver>.tar.gz
$ cd mercurial-<ver>
When installing, change python to python2.3 or python2.4 if 2.2 is the
default on your system.
To install system-wide:
$ python setup.py install --force
To install in your home directory (~/bin and ~/lib, actually), run:
$ python setup.py install --home=${HOME} --force
$ export PYTHONPATH=${HOME}/lib/python # (or lib64/ on some systems)
$ export PATH=${HOME}/bin:$PATH # add these to your .bashrc
And finally:
$ hg # test installation, show help
If you get complaints about missing modules, you probably haven't set
PYTHONPATH correctly.
Setting up a Mercurial project:
$ hg init project # creates project directory
$ cd project
# copy files in, edit them
$ hg add # add all unknown files
$ hg remove --after # remove deleted files
$ hg commit # commit all changes, edit changelog entry
Mercurial will look for a file named .hgignore in the root of your
repository which contains a set of regular expressions to ignore in
file paths.
Branching and merging:
$ hg clone linux linux-work # create a new branch
$ cd linux-work
$ <make changes>
$ hg commit
$ cd ../linux
$ hg pull ../linux-work # pull changesets from linux-work
$ hg merge # merge the new tip from linux-work into
# our working directory
$ hg commit # commit the result of the merge
Importing patches:
Fast:
$ patch < ../p/foo.patch
$ hg commit -A
Faster:
$ patch < ../p/foo.patch
$ hg commit `lsdiff -p1 ../p/foo.patch`
Fastest:
$ cat ../p/patchlist | xargs hg import -p1 -b ../p
Exporting a patch:
(make changes)
$ hg commit
$ hg tip
28237:747a537bd090880c29eae861df4d81b245aa0190
$ hg export 28237 > foo.patch # export changeset 28237
Network support:
# pull from the primary Mercurial repo
foo$ hg clone http://selenic.com/hg/
foo$ cd hg
# export your current repo via HTTP with browsable interface
foo$ hg serve -n "My repo" -p 80
# pushing changes to a remote repo with SSH
foo$ hg push ssh://user@example.com/~/hg/
# merge changes from a remote machine
bar$ hg pull http://foo/
bar$ hg merge # merge changes into your working directory
# Set up a CGI server on your webserver
foo$ cp hgweb.cgi ~/public_html/hg/index.cgi
foo$ emacs ~/public_html/hg/index.cgi # adjust the defaults
For more info:
Documentation in doc/
Mercurial website at http://selenic.com/mercurial