bundle2: inline changegroup.readexactly()
Profiling reveals this loop is pretty tight. Literally any
function call elimination can make a big difference.
This commit inlines the relatively trivial changegroup.readexactly()
method inside the loop.
The results with `hg perfbundleread` on a bundle of the Firefox repo
speak for themselves:
! read(8k)
! wall 0.679730 comb 0.680000 user 0.140000 sys 0.540000 (best of 15)
! read(16k)
! wall 0.577228 comb 0.570000 user 0.080000 sys 0.490000 (best of 17)
! read(32k)
! wall 0.516060 comb 0.520000 user 0.040000 sys 0.480000 (best of 20)
! read(128k)
! wall 0.496378 comb 0.490000 user 0.010000 sys 0.480000 (best of 20)
! bundle2 iterparts()
! wall 3.460903 comb 3.460000 user 2.760000 sys 0.700000 (best of 3)
! wall 3.056811 comb 3.050000 user 2.340000 sys 0.710000 (best of 4)
! bundle2 iterparts() seekable
! wall 4.312722 comb 4.310000 user 3.480000 sys 0.830000 (best of 3)
! wall 4.007676 comb 4.000000 user 3.170000 sys 0.830000 (best of 3)
! bundle2 part seek()
! wall 6.754764 comb 6.740000 user 3.970000 sys 2.770000 (best of 3)
! wall 6.267110 comb 6.250000 user 3.480000 sys 2.770000 (best of 3)
! bundle2 part read(8k)
! wall 3.668004 comb 3.660000 user 2.960000 sys 0.700000 (best of 3)
! wall 3.404164 comb 3.400000 user 2.650000 sys 0.750000 (best of 3)
! bundle2 part read(16k)
! wall 3.489196 comb 3.480000 user 2.750000 sys 0.730000 (best of 3)
! wall 3.197972 comb 3.200000 user 2.490000 sys 0.710000 (best of 4)
! bundle2 part read(32k)
! wall 3.388569 comb 3.380000 user 2.640000 sys 0.740000 (best of 3)
! wall 3.060557 comb 3.060000 user 2.340000 sys 0.720000 (best of 4)
! bundle2 part read(128k)
! wall 3.276415 comb 3.270000 user 2.560000 sys 0.710000 (best of 4)
! wall 2.952209 comb 2.950000 user 2.230000 sys 0.720000 (best of 4)
Differential Revision: https://phab.mercurial-scm.org/D1392
$ cat >> $HGRCPATH <<EOF
> [format]
> usegeneraldelta=yes
> [extensions]
> rebase=
> drawdag=$TESTDIR/drawdag.py
> [alias]
> tglog = log -G --template "{rev}: '{desc}' {branches}\n"
> EOF
$ hg init repo
$ cd repo
$ echo A > a
$ echo >> a
$ hg ci -Am A
adding a
$ echo B > a
$ echo >> a
$ hg ci -m B
$ echo C > a
$ echo >> a
$ hg ci -m C
$ hg up -q -C 0
$ echo D >> a
$ hg ci -Am AD
created new head
$ hg tglog
@ 3: 'AD'
|
| o 2: 'C'
| |
| o 1: 'B'
|/
o 0: 'A'
$ hg rebase -s 1 -d 3
rebasing 1:0f4f7cb4f549 "B"
merging a
rebasing 2:30ae917c0e4f "C"
merging a
saved backup bundle to $TESTTMP/repo/.hg/strip-backup/0f4f7cb4f549-82b3b163-rebase.hg (glob)
$ hg tglog
o 3: 'C'
|
o 2: 'B'
|
@ 1: 'AD'
|
o 0: 'A'
$ cd ..
Test rebasing of merges with ancestors of the rebase destination - a situation
that often happens when trying to recover from repeated merging with a mainline
branch.
The test case creates a dev branch that contains a couple of merges from the
default branch. When rebasing to the default branch, these merges would be
merges with ancestors on the same branch. The merges _could_ contain some
interesting conflict resolutions or additional changes in the merge commit, but
that is mixed up with the actual merge stuff and there is in general no way to
separate them.
Note: The dev branch contains _no_ changes to f-default. It might be unclear
how rebasing of ancestor merges should be handled, but the current behavior
with spurious prompts for conflicts in files that didn't change seems very
wrong.
$ hg init ancestor-merge
$ cd ancestor-merge
$ touch f-default
$ hg ci -Aqm 'default: create f-default'
$ hg branch -q dev
$ hg ci -qm 'dev: create branch'
$ echo stuff > f-dev
$ hg ci -Aqm 'dev: f-dev stuff'
$ hg up -q default
$ echo stuff > f-default
$ hg ci -m 'default: f-default stuff'
$ hg up -q dev
$ hg merge -q default
$ hg ci -m 'dev: merge default'
$ hg up -q default
$ hg rm f-default
$ hg ci -m 'default: remove f-default'
$ hg up -q dev
$ hg merge -q default
$ hg ci -m 'dev: merge default'
$ hg up -q default
$ echo stuff > f-other
$ hg ci -Aqm 'default: f-other stuff'
$ hg tglog
@ 7: 'default: f-other stuff'
|
| o 6: 'dev: merge default' dev
|/|
o | 5: 'default: remove f-default'
| |
| o 4: 'dev: merge default' dev
|/|
o | 3: 'default: f-default stuff'
| |
| o 2: 'dev: f-dev stuff' dev
| |
| o 1: 'dev: create branch' dev
|/
o 0: 'default: create f-default'
$ hg clone -qU . ../ancestor-merge-2
Full rebase all the way back from branching point:
$ hg rebase -r 'only(dev,default)' -d default --config ui.interactive=True << EOF
> c
> EOF
rebasing 1:1d1a643d390e "dev: create branch"
note: rebase of 1:1d1a643d390e created no changes to commit
rebasing 2:ec2c14fb2984 "dev: f-dev stuff"
rebasing 4:4b019212aaf6 "dev: merge default"
other [source] changed f-default which local [dest] deleted
use (c)hanged version, leave (d)eleted, or leave (u)nresolved? c
rebasing 6:9455ee510502 "dev: merge default"
saved backup bundle to $TESTTMP/ancestor-merge/.hg/strip-backup/1d1a643d390e-43e9e04b-rebase.hg (glob)
$ hg tglog
o 6: 'dev: merge default'
|
o 5: 'dev: merge default'
|
o 4: 'dev: f-dev stuff'
|
@ 3: 'default: f-other stuff'
|
o 2: 'default: remove f-default'
|
o 1: 'default: f-default stuff'
|
o 0: 'default: create f-default'
Grafty cherry picking rebasing:
$ cd ../ancestor-merge-2
$ hg phase -fdr0:
$ hg rebase -r 'children(only(dev,default))' -d default --config ui.interactive=True << EOF
> c
> EOF
rebasing 2:ec2c14fb2984 "dev: f-dev stuff"
rebasing 4:4b019212aaf6 "dev: merge default"
other [source] changed f-default which local [dest] deleted
use (c)hanged version, leave (d)eleted, or leave (u)nresolved? c
rebasing 6:9455ee510502 "dev: merge default"
saved backup bundle to $TESTTMP/ancestor-merge-2/.hg/strip-backup/ec2c14fb2984-62d0b222-rebase.hg (glob)
$ hg tglog
o 7: 'dev: merge default'
|
o 6: 'dev: merge default'
|
o 5: 'dev: f-dev stuff'
|
o 4: 'default: f-other stuff'
|
o 3: 'default: remove f-default'
|
o 2: 'default: f-default stuff'
|
| o 1: 'dev: create branch' dev
|/
o 0: 'default: create f-default'
$ cd ..
Test order of parents of rebased merged with un-rebased changes as p1.
$ hg init parentorder
$ cd parentorder
$ touch f
$ hg ci -Aqm common
$ touch change
$ hg ci -Aqm change
$ touch target
$ hg ci -Aqm target
$ hg up -qr 0
$ touch outside
$ hg ci -Aqm outside
$ hg merge -qr 1
$ hg ci -m 'merge p1 3=outside p2 1=ancestor'
$ hg par
changeset: 4:6990226659be
tag: tip
parent: 3:f59da8fc0fcf
parent: 1:dd40c13f7a6f
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: merge p1 3=outside p2 1=ancestor
$ hg up -qr 1
$ hg merge -qr 3
$ hg ci -qm 'merge p1 1=ancestor p2 3=outside'
$ hg par
changeset: 5:a57575f79074
tag: tip
parent: 1:dd40c13f7a6f
parent: 3:f59da8fc0fcf
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: merge p1 1=ancestor p2 3=outside
$ hg tglog
@ 5: 'merge p1 1=ancestor p2 3=outside'
|\
+---o 4: 'merge p1 3=outside p2 1=ancestor'
| |/
| o 3: 'outside'
| |
+---o 2: 'target'
| |
o | 1: 'change'
|/
o 0: 'common'
$ hg rebase -r 4 -d 2
rebasing 4:6990226659be "merge p1 3=outside p2 1=ancestor"
saved backup bundle to $TESTTMP/parentorder/.hg/strip-backup/6990226659be-4d67a0d3-rebase.hg (glob)
$ hg tip
changeset: 5:cca50676b1c5
tag: tip
parent: 2:a60552eb93fb
parent: 3:f59da8fc0fcf
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: merge p1 3=outside p2 1=ancestor
$ hg rebase -r 4 -d 2
rebasing 4:a57575f79074 "merge p1 1=ancestor p2 3=outside"
saved backup bundle to $TESTTMP/parentorder/.hg/strip-backup/a57575f79074-385426e5-rebase.hg (glob)
$ hg tip
changeset: 5:f9daf77ffe76
tag: tip
parent: 2:a60552eb93fb
parent: 3:f59da8fc0fcf
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: merge p1 1=ancestor p2 3=outside
$ hg tglog
@ 5: 'merge p1 1=ancestor p2 3=outside'
|\
+---o 4: 'merge p1 3=outside p2 1=ancestor'
| |/
| o 3: 'outside'
| |
o | 2: 'target'
| |
o | 1: 'change'
|/
o 0: 'common'
rebase of merge of ancestors
$ hg up -qr 2
$ hg merge -qr 3
$ echo 'other change while merging future "rebase ancestors"' > other
$ hg ci -Aqm 'merge rebase ancestors'
$ hg rebase -d 5 -v
rebasing 6:4c5f12f25ebe "merge rebase ancestors" (tip)
resolving manifests
removing other
note: merging f9daf77ffe76+ and 4c5f12f25ebe using bids from ancestors a60552eb93fb and f59da8fc0fcf
calculating bids for ancestor a60552eb93fb
resolving manifests
calculating bids for ancestor f59da8fc0fcf
resolving manifests
auction for merging merge bids
other: consensus for g
end of auction
getting other
committing files:
other
committing manifest
committing changelog
rebase merging completed
1 changesets found
uncompressed size of bundle content:
199 (changelog)
216 (manifests)
182 other
saved backup bundle to $TESTTMP/parentorder/.hg/strip-backup/4c5f12f25ebe-f46990e5-rebase.hg (glob)
1 changesets found
uncompressed size of bundle content:
254 (changelog)
167 (manifests)
182 other
adding branch
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
rebase completed
$ hg tglog
@ 6: 'merge rebase ancestors'
|
o 5: 'merge p1 1=ancestor p2 3=outside'
|\
+---o 4: 'merge p1 3=outside p2 1=ancestor'
| |/
| o 3: 'outside'
| |
o | 2: 'target'
| |
o | 1: 'change'
|/
o 0: 'common'
Due to the limitation of 3-way merge algorithm (1 merge base), rebasing a merge
may include unwanted content:
$ hg init $TESTTMP/dual-merge-base1
$ cd $TESTTMP/dual-merge-base1
$ hg debugdrawdag <<'EOS'
> F
> /|
> D E
> | |
> B C
> |/
> A Z
> |/
> R
> EOS
$ hg rebase -r D+E+F -d Z
rebasing 5:5f2c926dfecf "D" (D)
rebasing 6:b296604d9846 "E" (E)
rebasing 7:caa9781e507d "F" (F tip)
abort: rebasing 7:caa9781e507d will include unwanted changes from 4:d6003a550c2c or 3:c1e6b162678d
[255]
The warning does not get printed if there is no unwanted change detected:
$ hg init $TESTTMP/dual-merge-base2
$ cd $TESTTMP/dual-merge-base2
$ hg debugdrawdag <<'EOS'
> D
> /|
> B C
> |/
> A Z
> |/
> R
> EOS
$ hg rebase -r B+C+D -d Z
rebasing 3:c1e6b162678d "B" (B)
rebasing 4:d6003a550c2c "C" (C)
rebasing 5:c8f78076273e "D" (D tip)
saved backup bundle to $TESTTMP/dual-merge-base2/.hg/strip-backup/d6003a550c2c-6f1424b6-rebase.hg (glob)
$ hg manifest -r 'desc(D)'
B
C
R
Z
The merge base could be different from old p1 (changed parent becomes new p1):
$ hg init $TESTTMP/chosen-merge-base1
$ cd $TESTTMP/chosen-merge-base1
$ hg debugdrawdag <<'EOS'
> F
> /|
> D E
> | |
> B C Z
> EOS
$ hg rebase -r D+F -d Z
rebasing 3:004dc1679908 "D" (D)
rebasing 5:4be4cbf6f206 "F" (F tip)
saved backup bundle to $TESTTMP/chosen-merge-base1/.hg/strip-backup/004dc1679908-06a66a3c-rebase.hg (glob)
$ hg manifest -r 'desc(F)'
C
D
E
Z
$ hg log -r `hg log -r 'desc(F)' -T '{p1node}'` -T '{desc}\n'
D
$ hg init $TESTTMP/chosen-merge-base2
$ cd $TESTTMP/chosen-merge-base2
$ hg debugdrawdag <<'EOS'
> F
> /|
> D E
> | |
> B C Z
> EOS
$ hg rebase -r E+F -d Z
rebasing 4:974e4943c210 "E" (E)
rebasing 5:4be4cbf6f206 "F" (F tip)
saved backup bundle to $TESTTMP/chosen-merge-base2/.hg/strip-backup/974e4943c210-b2874da5-rebase.hg (glob)
$ hg manifest -r 'desc(F)'
B
D
E
Z
$ hg log -r `hg log -r 'desc(F)' -T '{p1node}'` -T '{desc}\n'
E