dirstate walking optimizations
The repo walking code introduces a number of calls to dirstate.map.copy(),
significantly slowing down the walk on large trees. When a list of
files is passed to the walking code, we should only look at map entries
relevant to the file list passed in.
dirstate.filterfiles() is added to return a subset of the dirstate map.
The subset includes in files passed in, and if one of the files requested
is actually a directory, it includes any files inside that directory tree.
This brings the time for hg diff Makefile down from 1.7s to .3s on
a linux kernel repo.
Also, the diff command was unconditionally calling makewalk, leading
to an extra pass through repo.changes. This patch avoids the call
to makewalk when commands.diff isn't given a list of patterns, cutting
the time for hg diff (with no args) in half.
Index: mine/mercurial/hg.py
===================================================================
+ hg init
+ hg add a
+ hg commit -m 1 -d 0 0
+ hg status
+ hg copy a b
+ hg status
A b
+ hg --debug commit -m 2 -d 0 0
b
b: copy a:b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3
+ hg history
changeset: 1:3b5b84850bbe
tag: tip
user: test
date: Thu Jan 1 00:00:00 1970
summary: 2
changeset: 0:c19d34741b0a
user: test
date: Thu Jan 1 00:00:00 1970
summary: 1
+ hg log a
changeset: 0:c19d34741b0a
user: test
date: Thu Jan 1 00:00:00 1970
summary: 1
566e338d09a089ba737c21e0d3759980 .hg/data/b.d
3268d2f51b2d2d423ff01b59eb6fbb14 bsum
70909ca2ecf494c71e9184b445e040ee asum
+ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
2 files, 2 changesets, 2 total revisions