branchmap: Save changectx creation during update
The newly introduced `branchmap` function allows us to skip the
creation of changectx objects. This speeds up the construction of
the branchmap.
On the mozilla repository (117293 changesets, 15490 mutable)
Before:
! impactable 19.9
! mutable 0.576
! unserved 3.16
After:
! impactable 7.03 (2.8x faster)
! mutable 0.352 (1.6x)
! unserved 1.15 (2.7x)
On the cpython repository (81418 changesets, 6418 mutable)
Before:
! impactable 15.9
! mutable 0.451
! unserved 0.861
After:
! impactable 6.55 (2.4x faster)
! mutable 0.170 (2.6x faster)
! unserved 0.289 (2.9x faster)
On the pypy repository (58852 changesets)
Before:
! impactable 13.6
After:
! impactable 6.17 (2.2x faster)
On my Mercurial repository (18295 changesets, 2210 mutable)
Before:
! impactable 23.9
! mutable 0.368
! unserved 0.057
After:
! impactable 1.31 (18x faster)
! mutable 0.042 (8.7x)
! unserved 0.025 (2.2x)
$ HGENCODING=utf-8
$ export HGENCODING
$ try() {
> hg debugrevspec --debug $@
> }
$ log() {
> hg log --template '{rev}\n' -r "$1"
> }
$ hg init repo
$ cd repo
$ try 'p1()'
(func
('symbol', 'p1')
None)
$ try 'p2()'
(func
('symbol', 'p2')
None)
$ try 'parents()'
(func
('symbol', 'parents')
None)
null revision
$ log 'p1()'
$ log 'p2()'
$ log 'parents()'
working dir with a single parent
$ echo a > a
$ hg ci -Aqm0
$ log 'p1()'
0
$ log 'tag() and p1()'
$ log 'p2()'
$ log 'parents()'
0
$ log 'tag() and parents()'
merge in progress
$ echo b > b
$ hg ci -Aqm1
$ hg up -q 0
$ echo c > c
$ hg ci -Aqm2
$ hg merge -q
$ log 'p1()'
2
$ log 'p2()'
1
$ log 'tag() and p2()'
$ log 'parents()'
1
2
$ cd ..