Optimize dirstate walking
This generally cuts the time for hg status/diff in half, from 2s down to 1s.
The main parts I'm trying to optimize are:
1) os.walk stats every file. dirstate.changes then stats every file again.
2) os.walk yields every file and subdir to dirstate.traverse who yields every
file and everything in the dirstate map. dirstate.walk then
filters this mass and yields every file to the caller. There should be
fewer steps in here, and fewer duplicate strings yielded.
3) dirstate.walk runs util.unique on the results from dirstate.traverse,
even though it is also passing things through dirstate.seen to look for
duplicates.
I've turned os.walk into something hg specific that takes all the dirstate
ignore and matching rules into account. The new function also takes an
function arg (statmatch()) the caller supplies to help filter out
files it doesn't care about. dirstate.changes uses this to update state
for each file, avoiding the second stat call.
dirstate.walk is changed to turn the match function it is passed into
a statmatch function. The only real difference is that a statmatch
function takes the stat data as a second parameter. It now calls
dirstate.walkhelper, who requires a statmatch function to be passed.
This fails test-walk, but right now I think this is from a sorting error
fixed by this patch.
Index: crew/mercurial/dirstate.py
===================================================================
Andrea Arcangeli <andrea at suse.de>
Thomas Arendsen Hein <thomas at intevation.de>
Goffredo Baroncelli <kreijack at libero.it>
Muli Ben-Yehuda <mulix at mulix.org>
Mikael Berthe <mikael at lilotux.net>
Vincent Danjean <vdanjean.ml at free.fr>
Jake Edge <jake at edge2.net>
Michael Fetterman <michael.fetterman at intel.com>
Edouard Gomez <ed.gomez at free.fr>
Alecs King <alecsk at gmail.com>
Vadim Lebedev <vadim at mbdsys.com>
Christopher Li <hg at chrisli.org>
Chris Mason <mason at suse.com>
Wojciech Milkowski <wmilkowski at interia.pl>
Chad Netzer <chad.netzer at gmail.com>
Bryan O'Sullivan <bos at serpentine.com>
Vicent Seguí Pascual <vseguip at gmail.com>
Sean Perry <shaleh at speakeasy.net>
Nguyen Anh Quynh <aquynh at gmail.com>
Arun Sharma <arun at sharma-home.net>
Josef "Jeff" Sipek <jeffpc@optonline.net>
TK Soh <teekaysoh@yahoo.com>
Kevin Smith <yarcs at qualitycode.com>
Radoslaw Szkodzinski <astralstorm at gorzow.mm.pl>
Samuel Tardieu <sam at rfc1149.net>
K Thananchayan <thananck at yahoo.com>
Andrew Thompson <andrewkt at aktzero.com>
Michael S. Tsirkin <mst at mellanox.co.il>
Rafael Villar Burke <pachi at mmn-arquitectos.com>
Tristan Wibberley <tristan at wibberley.org>
Mark Williamson <mark.williamson at cl.cam.ac.uk>
If you are a contributor and don't see your name here, please let me know.