view README @ 18878:3cfaace0441e

copies._forwardcopies: use set operations to find missing files

This is a performance win for a number of reasons:
- We don't iterate over contexts, which avoids a completely unnecessary sorted
  call + the O(number of files) abstraction cost of doing that.
- We don't check membership in a context, which avoids another
  O(number of files) abstraction cost.
- We iterate over the manifests in C instead of Python.

For a large repo with 170,000 files, this improves perfpathcopies from 0.34
seconds to 0.07. Anything that uses pathcopies, such as rebase or diff --git
between two revisions, benefits.

Mercurial
=========

Mercurial is a fast, easy to use, distributed revision control tool
for software developers.

Basic install:

 $ make            # see install targets
 $ make install    # do a system-wide install
 $ hg debuginstall # sanity-check setup
 $ hg              # see help

Running without installing:

 $ make local      # build for inplace usage
 $ ./hg --version  # should show the latest version

See http://mercurial.selenic.com/ for detailed installation
instructions, platform-specific notes, and Mercurial user information.