view README @ 31208:fc57a8b95f1b

dirstate: avoid unnecessary load+dump during backup

Previously, dirstate.savebackup unconditionally dumps the dirstate map to
disk. It may require loading dirstate first to be able to dump it. Those
operations could be expensive if the dirstate is big, and could be avoided
if we know the dirstate file is up-to-date.

This patch avoids the read and write if the dirstate is clean. In that case,
we just do a plain copy without any serialization.

This should make commands which use transactions but do not touch dirstate
faster. For example, "hg bookmark -r REV NAME".

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 https://mercurial-scm.org/ for detailed installation
instructions, platform-specific notes, and Mercurial user information.