dirstate: when calling rebuild(), avoid some N^2 codepaths
I had a user repo with 200k files in it. Calling `hg debugrebuilddirstate` took
tens of minutes (I didn't wait for it). In that situation,
changedfiles==allfiles, and both are lists. This meant that we had to run an
average of 100k comparisons, for each of 200k files, just to check whether a
file needed to have normallookup called (it always did), or drop.
While it's probably not a huge issue, in my very awkward synthetic benchmark I
wrote (not using a benchmark library or anything), I was seeing some slowdowns
for small-changedfiles and very-large-allfiles invocations, with an inflection
somewhere around 10 items in changedfiles (regardless of the size of allfiles);
above 10 items in changedfiles, the new code appears to always be faster. For
the case of 50k files in changedfiles and the same items in allfiles, I'm seeing
differences of 15s of just running comparisons vs. 0.003793s. I haven't bothered
to run a comparison of 200k items in changedfiles and allfiles. :)
Differential Revision: https://phab.mercurial-scm.org/D7665
#require no-windows
$ . "$TESTDIR/remotefilelog-library.sh"
$ hg init master
$ cd master
$ cat >> .hg/hgrc <<EOF
> [remotefilelog]
> server=True
> EOF
$ echo x > x
$ echo z > z
$ hg commit -qAm x
$ echo x2 > x
$ echo y > y
$ hg commit -qAm y
$ hg bookmark foo
$ cd ..
# prefetch a revision
$ hgcloneshallow ssh://user@dummy/master shallow --noupdate
streaming all changes
2 files to transfer, 528 bytes of data
transferred 528 bytes in * seconds (*/sec) (glob)
searching for changes
no changes found
$ cd shallow
$ hg prefetch -r 0
2 files fetched over 1 fetches - (2 misses, 0.00% hit ratio) over *s (glob)
$ hg cat -r 0 x
x
# prefetch with base
$ clearcache
$ hg prefetch -r 0::1 -b 0
2 files fetched over 1 fetches - (2 misses, 0.00% hit ratio) over *s (glob)
$ hg cat -r 1 x
x2
$ hg cat -r 1 y
y
$ hg cat -r 0 x
x
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
$ hg cat -r 0 z
z
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
$ hg prefetch -r 0::1 --base 0
$ hg prefetch -r 0::1 -b 1
$ hg prefetch -r 0::1
# prefetch a range of revisions
$ clearcache
$ hg prefetch -r 0::1
4 files fetched over 1 fetches - (4 misses, 0.00% hit ratio) over *s (glob)
$ hg cat -r 0 x
x
$ hg cat -r 1 x
x2
# prefetch certain files
$ clearcache
$ hg prefetch -r 1 x
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
$ hg cat -r 1 x
x2
$ hg cat -r 1 y
y
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
# prefetch on pull when configured
$ printf "[remotefilelog]\npullprefetch=bookmark()\n" >> .hg/hgrc
$ hg strip tip
saved backup bundle to $TESTTMP/shallow/.hg/strip-backup/109c3a557a73-3f43405e-backup.hg (glob)
$ clearcache
$ hg pull
pulling from ssh://user@dummy/master
searching for changes
adding changesets
adding manifests
adding file changes
updating bookmark foo
added 1 changesets with 0 changes to 0 files
new changesets 109c3a557a73
(run 'hg update' to get a working copy)
prefetching file contents
3 files fetched over 1 fetches - (3 misses, 0.00% hit ratio) over *s (glob)
$ hg up tip
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
# prefetch only fetches changes not in working copy
$ hg strip tip
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
saved backup bundle to $TESTTMP/shallow/.hg/strip-backup/109c3a557a73-3f43405e-backup.hg (glob)
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
$ clearcache
$ hg pull
pulling from ssh://user@dummy/master
searching for changes
adding changesets
adding manifests
adding file changes
updating bookmark foo
added 1 changesets with 0 changes to 0 files
new changesets 109c3a557a73
(run 'hg update' to get a working copy)
prefetching file contents
2 files fetched over 1 fetches - (2 misses, 0.00% hit ratio) over *s (glob)
# Make some local commits that produce the same file versions as are on the
# server. To simulate a situation where we have local commits that were somehow
# pushed, and we will soon pull.
$ hg prefetch -r 'all()'
2 files fetched over 1 fetches - (2 misses, 0.00% hit ratio) over *s (glob)
$ hg strip -q -r 0
$ echo x > x
$ echo z > z
$ hg commit -qAm x
$ echo x2 > x
$ echo y > y
$ hg commit -qAm y
# prefetch server versions, even if local versions are available
$ clearcache
$ hg strip -q tip
$ hg pull
pulling from ssh://user@dummy/master
searching for changes
adding changesets
adding manifests
adding file changes
updating bookmark foo
added 1 changesets with 0 changes to 0 files
new changesets 109c3a557a73
1 local changesets published (?)
(run 'hg update' to get a working copy)
prefetching file contents
2 files fetched over 1 fetches - (2 misses, 0.00% hit ratio) over *s (glob)
$ cd ..
# Prefetch unknown files during checkout
$ hgcloneshallow ssh://user@dummy/master shallow2
streaming all changes
2 files to transfer, 528 bytes of data
transferred 528 bytes in * seconds * (glob)
searching for changes
no changes found
updating to branch default
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over * (glob)
$ cd shallow2
$ hg up -q null
$ echo x > x
$ echo y > y
$ echo z > z
$ clearcache
$ hg up tip
x: untracked file differs
3 files fetched over 1 fetches - (3 misses, 0.00% hit ratio) over * (glob)
abort: untracked files in working directory differ from files in requested revision
[255]
$ hg revert --all
# Test batch fetching of lookup files during hg status
$ hg up --clean tip
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg debugrebuilddirstate
$ clearcache
$ hg status
3 files fetched over 1 fetches - (3 misses, 0.00% hit ratio) over * (glob)
# Prefetch during addrename detection
$ hg up -q --clean tip
$ hg revert --all
$ mv x x2
$ mv y y2
$ mv z z2
$ echo a > a
$ hg add a
$ rm a
$ clearcache
$ hg addremove -s 50 > /dev/null
3 files fetched over 1 fetches - (3 misses, 0.00% hit ratio) over * (glob)
$ hg revert --all
forgetting x2
forgetting y2
forgetting z2
undeleting x
undeleting y
undeleting z
# Revert across double renames. Note: the scary "abort", error is because
# https://bz.mercurial-scm.org/5419 .
$ cd ../master
$ hg mv z z2
$ hg commit -m 'move z -> z2'
$ cd ../shallow2
$ hg pull -q
$ clearcache
$ hg mv y y2
y2: not overwriting - file exists
('hg rename --after' to record the rename)
[1]
$ hg mv x x2
x2: not overwriting - file exists
('hg rename --after' to record the rename)
[1]
$ hg mv z2 z3
z2: not copying - file is not managed
abort: no files to copy
[255]
$ hg revert -a -r 1 || true
3 files fetched over 1 fetches - (3 misses, 0.00% hit ratio) over * (glob)
abort: z2@109c3a557a73: not found in manifest! (?)