match: convert O(n) to O(log n) in exactmatcher.visitchildrenset
When using narrow, during rebase this is called (at least) once per directory in
the set of files in the commit being rebased. Every time it's called, we did the
set arithmetic (now extracted and cached), which was probably pretty cheap but
not necessary to repeat each time, looped over every item in the matcher and
kept things that started with the directory we were querying.
With very large narrowspecs, and a commit that touched a file in a large number
of directories, this was slow. In a pathological repo, the rebase of a single
commit (that touched over 17k files, I believe in approximately as many
directories) with a narrowspec that had >32k entries took 8,246s of profiled
time, with 5,007s of that spent in visitchildrenset (transitively). With this
change, the time spent in visitchildrenset is less than 34s (which is where my
profile cut off). Most of the remaining time was network access due to our
custom remotefilelog-based setup not properly prefetching.
Differential Revision: https://phab.mercurial-scm.org/D10294
$ . "$TESTDIR/narrow-library.sh"
create full repo
$ hg init master
$ cd master
$ mkdir inside
$ echo inside > inside/f1
$ mkdir outside
$ echo outside > outside/f2
$ hg ci -Aqm 'initial'
$ hg mv outside/f2 inside/f2
$ hg ci -qm 'move f2 from outside'
$ echo modified > inside/f2
$ hg ci -qm 'modify inside/f2'
$ mkdir outside
$ echo new > outside/f3
$ hg ci -Aqm 'add outside/f3'
$ cd ..
$ hg clone --narrow ssh://user@dummy/master narrow --include inside -r 2
adding changesets
adding manifests
adding file changes
added 3 changesets with 3 changes to 2 files
new changesets *:* (glob)
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd narrow
$ hg co 'desc("move f2")'
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg status
$ hg diff
$ hg diff --change . --git
diff --git a/inside/f2 b/inside/f2
new file mode 100644
--- /dev/null
+++ b/inside/f2
@@ -0,0 +1,1 @@
+outside
$ hg log --follow inside/f2 -r tip
changeset: 2:bcfb756e0ca9
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: modify inside/f2
changeset: 1:5a016133b2bb
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: move f2 from outside
$ echo new > inside/f4
$ hg ci -Aqm 'add inside/f4'
$ hg pull -q
$ hg --config extensions.rebase= rebase -d tip
rebasing 3:4f84b666728c "add inside/f4"
saved backup bundle to $TESTTMP/narrow/.hg/strip-backup/4f84b666728c-4269b76e-rebase.hg
$ hg co -q 0
$ echo modified > inside/f1
$ hg ci -qm 'modify inside/f1'
$ echo new > inside/f5
$ hg ci -Aqm 'add inside/f5'
$ hg --config extensions.rebase= rebase -d 'public()' -r .
rebasing 6:610b60178c28 tip "add inside/f5"
saved backup bundle to $TESTTMP/narrow/.hg/strip-backup/610b60178c28-65716a78-rebase.hg