changegroup: compute seen files as changesets are added (
issue4750)
Before this patch, addchangegroup() would walk the changelog and compute
the set of seen files between applying changesets and applying
manifests. When cloning large repositories such as mozilla-central,
this consumed a non-trivial amount of time. On my MBP, this walk takes
~10s. On a dainty EC2 instance, this was measured to take ~125s! On the
latter machine, this delay was enough for the Mercurial server to
disconnect the client, thinking it had timed out, thus causing a clone
to abort.
This patch enables the changelog to compute the set of changed files as
new revisions are added. By doing so, we:
* avoid a potentially heavy computation between changelog and manifest
processing by spreading the computation across all changelog additions
* avoid extra reads from the changelog by operating on the data as it is
added
The downside of this is that the add revision callback does result in
extra I/O. Before, we would perform a flush (and subsequent read to
construct the full revision) when new delta chains were created. For
changelogs, this is typically every 2-4 revisions. Using the callback
guarantees there will be a flush after every added revision *and* an
open + read of the changelog to obtain the full revision in order to
read the added files. So, this increases the frequency of these
operations by the average chain length. In the future, the revlog
should be smart enough to know how to read revisions that haven't been
flushed yet, thus eliminating this extra I/O.
On my MBP, the total CPU times for an `hg unbundle` with a local
mozilla-central gzip bundle containing 251,934 changesets and 211,065
files did not have a statistically significant change with this patch,
holding steady around 360s. So, the increased revlog flushing did not
have an effect.
With this patch, there is no longer a visible pause between applying
changeset and manifest data. Before, it sure felt like Mercurial was
lethargic making this transition. Now, the transition is nearly
instantaneous, giving the impression that Mercurial is faster. Of course,
eliminating this pause means that the potential for network disconnect due
to channel inactivity during the changelog walk is eliminated as well.
And that is the impetus behind this change.
Test that qpush cleans things up if it doesn't complete
$ echo "[extensions]" >> $HGRCPATH
$ echo "mq=" >> $HGRCPATH
$ hg init repo
$ cd repo
$ echo foo > foo
$ hg ci -Am 'add foo'
adding foo
$ touch untracked-file
$ echo 'syntax: glob' > .hgignore
$ echo '.hgignore' >> .hgignore
$ hg qinit
test qpush on empty series
$ hg qpush
no patches in series
$ hg qnew patch1
$ echo >> foo
$ hg qrefresh -m 'patch 1'
$ hg qnew patch2
$ echo bar > bar
$ hg add bar
$ hg qrefresh -m 'patch 2'
$ hg qnew --config 'mq.plain=true' -U bad-patch
$ echo >> foo
$ hg qrefresh
$ hg qpop -a
popping bad-patch
popping patch2
popping patch1
patch queue now empty
$ $PYTHON -c 'print "\xe9"' > message
$ cat .hg/patches/bad-patch >> message
$ mv message .hg/patches/bad-patch
$ cat > $TESTTMP/wrapplayback.py <<EOF
> import os
> from mercurial import extensions, transaction
> def wrapplayback(orig,
> journal, report, opener, vfsmap, entries, backupentries,
> unlink=True):
> orig(journal, report, opener, vfsmap, entries, backupentries, unlink)
> # Touching files truncated at "transaction.abort" causes
> # forcible re-loading invalidated filecache properties
> # (including repo.changelog)
> for f, o, _ignore in entries:
> if o or not unlink:
> os.utime(opener.join(f), (0.0, 0.0))
> def extsetup(ui):
> extensions.wrapfunction(transaction, '_playback', wrapplayback)
> EOF
$ hg qpush -a --config extensions.wrapplayback=$TESTTMP/wrapplayback.py && echo 'qpush succeeded?!'
applying patch1
applying patch2
applying bad-patch
transaction abort!
rollback completed
cleaning up working directory...done
abort: decoding near '\xe9': 'ascii' codec can't decode byte 0xe9 in position 0: ordinal not in range(128)! (esc)
[255]
$ hg parents
changeset: 0:bbd179dfa0a7
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: add foo
test corrupt status file
$ hg qpush
applying patch1
now at: patch1
$ cp .hg/patches/status .hg/patches/status.orig
$ hg qpop
popping patch1
patch queue now empty
$ cp .hg/patches/status.orig .hg/patches/status
$ hg qpush
abort: working directory revision is not qtip
[255]
$ rm .hg/patches/status .hg/patches/status.orig
bar should be gone; other unknown/ignored files should still be around
$ hg status -A
? untracked-file
I .hgignore
C foo
preparing qpush of a missing patch
$ hg qpop -a
no patches applied
$ hg qpush
applying patch1
now at: patch1
$ rm .hg/patches/patch2
now we expect the push to fail, but it should NOT complain about patch1
$ hg qpush
applying patch2
unable to read patch2
now at: patch1
[1]
preparing qpush of missing patch with no patch applied
$ hg qpop -a
popping patch1
patch queue now empty
$ rm .hg/patches/patch1
qpush should fail the same way as below
$ hg qpush
applying patch1
unable to read patch1
[1]
Test qpush to a patch below the currently applied patch.
$ hg qq -c guardedseriesorder
$ hg qnew a
$ hg qguard +block
$ hg qnew b
$ hg qnew c
$ hg qpop -a
popping c
popping b
popping a
patch queue now empty
try to push and pop while a is guarded
$ hg qpush a
cannot push 'a' - guarded by '+block'
[1]
$ hg qpush -a
applying b
patch b is empty
applying c
patch c is empty
now at: c
now try it when a is unguarded, and we're at the top of the queue
$ hg qapplied -v
0 G a
1 A b
2 A c
$ hg qsel block
$ hg qpush b
abort: cannot push to a previous patch: b
[255]
$ hg qpush a
abort: cannot push to a previous patch: a
[255]
and now we try it one more time with a unguarded, while we're not at the top of the queue
$ hg qpop b
popping c
now at: b
$ hg qpush a
abort: cannot push to a previous patch: a
[255]
test qpop --force and backup files
$ hg qpop -a
popping b
patch queue now empty
$ hg qq --create force
$ echo a > a
$ echo b > b
$ echo c > c
$ hg ci -Am add a b c
$ echo a >> a
$ hg rm b
$ hg rm c
$ hg qnew p1
$ echo a >> a
$ echo bb > b
$ hg add b
$ echo cc > c
$ hg add c
$ hg qpop --force --verbose
saving current version of a as a.orig
saving current version of b as b.orig
saving current version of c as c.orig
popping p1
patch queue now empty
$ hg st
? a.orig
? b.orig
? c.orig
? untracked-file
$ cat a.orig
a
a
a
$ cat b.orig
bb
$ cat c.orig
cc
test qpop --force --no-backup
$ hg qpush
applying p1
now at: p1
$ rm a.orig
$ echo a >> a
$ hg qpop --force --no-backup --verbose
popping p1
patch queue now empty
$ test -f a.orig && echo 'error: backup with --no-backup'
[1]
test qpop --keep-changes
$ hg qpush
applying p1
now at: p1
$ hg qpop --keep-changes --force
abort: cannot use both --force and --keep-changes
[255]
$ echo a >> a
$ hg qpop --keep-changes
abort: local changes found, refresh first
[255]
$ hg revert -qa a
$ rm a
$ hg qpop --keep-changes
abort: local changes found, refresh first
[255]
$ hg rm -A a
$ hg qpop --keep-changes
abort: local changes found, refresh first
[255]
$ hg revert -qa a
$ echo b > b
$ hg add b
$ hg qpop --keep-changes
abort: local changes found, refresh first
[255]
$ hg forget b
$ echo d > d
$ hg add d
$ hg qpop --keep-changes
popping p1
patch queue now empty
$ hg forget d
$ rm d
test qpush --force and backup files
$ echo a >> a
$ hg qnew p2
$ echo b >> b
$ echo d > d
$ echo e > e
$ hg add d e
$ hg rm c
$ hg qnew p3
$ hg qpop -a
popping p3
popping p2
patch queue now empty
$ echo a >> a
$ echo b1 >> b
$ echo d1 > d
$ hg add d
$ echo e1 > e
$ hg qpush -a --force --verbose
applying p2
saving current version of a as a.orig
patching file a
committing files:
a
committing manifest
committing changelog
applying p3
saving current version of b as b.orig
saving current version of d as d.orig
patching file b
patching file c
patching file d
file d already exists
1 out of 1 hunks FAILED -- saving rejects to file d.rej
patching file e
file e already exists
1 out of 1 hunks FAILED -- saving rejects to file e.rej
patch failed to apply
committing files:
b
committing manifest
committing changelog
patch failed, rejects left in working directory
errors during apply, please fix and refresh p3
[2]
$ cat a.orig
a
a
$ cat b.orig
b
b1
$ cat d.orig
d1
test qpush --force --no-backup
$ hg revert -qa
$ hg qpop -a
popping p3
popping p2
patch queue now empty
$ echo a >> a
$ rm a.orig
$ hg qpush --force --no-backup --verbose
applying p2
patching file a
committing files:
a
committing manifest
committing changelog
now at: p2
$ test -f a.orig && echo 'error: backup with --no-backup'
[1]
test qgoto --force --no-backup
$ hg qpop
popping p2
patch queue now empty
$ echo a >> a
$ hg qgoto --force --no-backup p2 --verbose
applying p2
patching file a
committing files:
a
committing manifest
committing changelog
now at: p2
$ test -f a.orig && echo 'error: backup with --no-backup'
[1]
test qpush --keep-changes
$ hg qpush --keep-changes --force
abort: cannot use both --force and --keep-changes
[255]
$ hg qpush --keep-changes --exact
abort: cannot use --exact and --keep-changes together
[255]
$ echo b >> b
$ hg qpush --keep-changes
applying p3
abort: conflicting local changes found
(did you forget to qrefresh?)
[255]
$ rm b
$ hg qpush --keep-changes
applying p3
abort: conflicting local changes found
(did you forget to qrefresh?)
[255]
$ hg rm -A b
$ hg qpush --keep-changes
applying p3
abort: conflicting local changes found
(did you forget to qrefresh?)
[255]
$ hg revert -aq b
$ echo d > d
$ hg add d
$ hg qpush --keep-changes
applying p3
abort: conflicting local changes found
(did you forget to qrefresh?)
[255]
$ hg forget d
$ rm d
$ hg qpop
popping p2
patch queue now empty
$ echo b >> b
$ hg qpush -a --keep-changes
applying p2
applying p3
abort: conflicting local changes found
(did you forget to qrefresh?)
[255]
$ hg qtop
p2
$ hg parents --template "{rev} {desc}\n"
2 imported patch p2
$ hg st b
M b
$ cat b
b
b
test qgoto --keep-changes
$ hg revert -aq b
$ rm e
$ hg qgoto --keep-changes --force p3
abort: cannot use both --force and --keep-changes
[255]
$ echo a >> a
$ hg qgoto --keep-changes p3
applying p3
now at: p3
$ hg st a
M a
$ hg qgoto --keep-changes p2
popping p3
now at: p2
$ hg st a
M a
test mq.keepchanges setting
$ hg --config mq.keepchanges=1 qpush
applying p3
now at: p3
$ hg st a
M a
$ hg --config mq.keepchanges=1 qpop
popping p3
now at: p2
$ hg st a
M a
$ hg --config mq.keepchanges=1 qgoto p3
applying p3
now at: p3
$ hg st a
M a
$ echo b >> b
$ hg --config mq.keepchanges=1 qpop --force
popping p3
now at: p2
$ hg st b
$ hg --config mq.keepchanges=1 qpush --exact
abort: local changes found, refresh first
[255]
$ hg revert -qa a
$ hg qpop
popping p2
patch queue now empty
$ echo a >> a
$ hg --config mq.keepchanges=1 qpush --force
applying p2
now at: p2
$ hg st a
$ cd ..