bundle2: implement consume() API on unbundlepart
We want bundle parts to not be seekable by default. That means
eliminating the generic seek() method.
A common pattern in bundle2.py is to seek to the end of the part
data. This is mainly used by the part iteration code to ensure
the underlying stream is advanced to the next bundle part.
In this commit, we establish a dedicated API for consuming a
bundle2 part data. We switch users of seek() to it.
The old implementation of seek(0, os.SEEK_END) would effectively
call self.read(). The new implementation calls self.read(32768)
in a loop. The old implementation would therefore assemble a
buffer to hold all remaining data being seeked over. For seeking
over large bundle parts, this would involve a large allocation and
a lot of overhead to collect intermediate data! This overhead can
be seen in the results for `hg perfbundleread`:
! bundle2 iterparts()
! wall 10.891305 comb 10.820000 user 7.990000 sys 2.830000 (best of 3)
! wall 8.070791 comb 8.060000 user 7.180000 sys 0.880000 (best of 3)
! bundle2 part seek()
! wall 12.991478 comb 10.390000 user 7.720000 sys 2.670000 (best of 3)
! wall 10.370142 comb 10.350000 user 7.430000 sys 2.920000 (best of 3)
Of course, skipping over large payload data isn't likely very common.
So I doubt the performance wins will be observed in the wild.
Differential Revision: https://phab.mercurial-scm.org/D1388
Criss cross merging
$ hg init criss-cross
$ cd criss-cross
$ echo '0 base' > f1
$ echo '0 base' > f2
$ hg ci -Aqm '0 base'
$ echo '1 first change' > f1
$ hg ci -m '1 first change f1'
$ hg up -qr0
$ echo '2 first change' > f2
$ mkdir d1
$ echo '0 base' > d1/f3
$ echo '0 base' > d1/f4
$ hg add -q d1
$ hg ci -qm '2 first change f2'
$ hg merge -qr 1
$ hg rm d1/f3
$ hg mv -q d1 d2
$ hg ci -m '3 merge'
$ hg up -qr2
$ hg merge -qr1
$ hg ci -qm '4 merge'
$ echo '5 second change' > f1
$ hg ci -m '5 second change f1'
$ hg up -r3
2 files updated, 0 files merged, 2 files removed, 0 files unresolved
$ echo '6 second change' > f2
$ hg ci -m '6 second change f2'
$ hg log -G
@ changeset: 6:6373bbfdae1d
| tag: tip
| parent: 3:c202c8af058d
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: 6 second change f2
|
| o changeset: 5:e673248094b1
| | user: test
| | date: Thu Jan 01 00:00:00 1970 +0000
| | summary: 5 second change f1
| |
| o changeset: 4:177f58377c06
| |\ parent: 2:d1d156401c1b
| | | parent: 1:0f6b37dbe527
| | | user: test
| | | date: Thu Jan 01 00:00:00 1970 +0000
| | | summary: 4 merge
| | |
o---+ changeset: 3:c202c8af058d
| | | parent: 2:d1d156401c1b
|/ / parent: 1:0f6b37dbe527
| | user: test
| | date: Thu Jan 01 00:00:00 1970 +0000
| | summary: 3 merge
| |
| o changeset: 2:d1d156401c1b
| | parent: 0:40494bf2444c
| | user: test
| | date: Thu Jan 01 00:00:00 1970 +0000
| | summary: 2 first change f2
| |
o | changeset: 1:0f6b37dbe527
|/ user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: 1 first change f1
|
o changeset: 0:40494bf2444c
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 0 base
$ hg merge -v --debug --tool internal:dump 5 --config merge.preferancestor='!'
note: using 0f6b37dbe527 as ancestor of 6373bbfdae1d and e673248094b1
alternatively, use --config merge.preferancestor=d1d156401c1b
searching for copies back to rev 3
unmatched files in local:
d2/f4
unmatched files in other:
d1/f3
d1/f4
all copies found (* = to merge, ! = divergent, % = renamed and deleted):
src: 'd1/f4' -> dst: 'd2/f4'
checking for directory renames
discovered dir src: 'd1/' -> dst: 'd2/'
pending file src: 'd1/f3' -> dst: 'd2/f3'
pending file src: 'd1/f4' -> dst: 'd2/f4'
resolving manifests
branchmerge: True, force: False, partial: False
ancestor: 0f6b37dbe527, local: 6373bbfdae1d+, remote: e673248094b1
preserving d2/f4 for resolve of d2/f4
preserving f2 for resolve of f2
f1: remote is newer -> g
getting f1
d2/f3: local directory rename - get from d1/f3 -> dg
getting d1/f3 to d2/f3
d2/f4: local directory rename, both created -> m (premerge)
f2: versions differ -> m (premerge)
picked tool ':dump' for f2 (binary False symlink False changedelete False)
merging f2
my f2@6373bbfdae1d+ other f2@e673248094b1 ancestor f2@0f6b37dbe527
f2: versions differ -> m (merge)
picked tool ':dump' for f2 (binary False symlink False changedelete False)
my f2@6373bbfdae1d+ other f2@e673248094b1 ancestor f2@0f6b37dbe527
3 files updated, 0 files merged, 0 files removed, 1 files unresolved
use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
[1]
$ f --dump --recurse *
d2: directory with 2 files
d2/f3: (glob)
>>>
0 base
<<<
d2/f4: (glob)
>>>
0 base
<<<
f1:
>>>
5 second change
<<<
f2:
>>>
6 second change
<<<
f2.base:
>>>
0 base
<<<
f2.local:
>>>
6 second change
<<<
f2.orig:
>>>
6 second change
<<<
f2.other:
>>>
2 first change
<<<
$ hg up -qC .
$ hg merge -v --tool internal:dump 5 --config merge.preferancestor="null 40663881 3b08d"
note: using 0f6b37dbe527 as ancestor of 6373bbfdae1d and e673248094b1
alternatively, use --config merge.preferancestor=d1d156401c1b
resolving manifests
getting f1
getting d1/f3 to d2/f3
merging f2
3 files updated, 0 files merged, 0 files removed, 1 files unresolved
use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
[1]
Redo merge with merge.preferancestor="*" to enable bid merge
$ rm f*
$ hg up -qC .
$ hg merge -v --debug --tool internal:dump 5 --config merge.preferancestor="*"
note: merging 6373bbfdae1d+ and e673248094b1 using bids from ancestors 0f6b37dbe527 and d1d156401c1b
calculating bids for ancestor 0f6b37dbe527
searching for copies back to rev 3
unmatched files in local:
d2/f4
unmatched files in other:
d1/f3
d1/f4
all copies found (* = to merge, ! = divergent, % = renamed and deleted):
src: 'd1/f4' -> dst: 'd2/f4'
checking for directory renames
discovered dir src: 'd1/' -> dst: 'd2/'
pending file src: 'd1/f3' -> dst: 'd2/f3'
pending file src: 'd1/f4' -> dst: 'd2/f4'
resolving manifests
branchmerge: True, force: False, partial: False
ancestor: 0f6b37dbe527, local: 6373bbfdae1d+, remote: e673248094b1
d2/f3: local directory rename - get from d1/f3 -> dg
d2/f4: local directory rename, both created -> m
f1: remote is newer -> g
f2: versions differ -> m
calculating bids for ancestor d1d156401c1b
searching for copies back to rev 3
unmatched files in local:
d2/f4
all copies found (* = to merge, ! = divergent, % = renamed and deleted):
src: 'd1/f4' -> dst: 'd2/f4'
checking for directory renames
discovered dir src: 'd1/' -> dst: 'd2/'
resolving manifests
branchmerge: True, force: False, partial: False
ancestor: d1d156401c1b, local: 6373bbfdae1d+, remote: e673248094b1
f1: versions differ -> m
f2: remote unchanged -> k
auction for merging merge bids
d2/f3: consensus for dg
d2/f4: consensus for m
f1: picking 'get' action
f2: picking 'keep' action
end of auction
preserving d2/f4 for resolve of d2/f4
f1: remote is newer -> g
getting f1
f2: remote unchanged -> k
d2/f3: local directory rename - get from d1/f3 -> dg
getting d1/f3 to d2/f3
d2/f4: local directory rename, both created -> m (premerge)
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ f --dump --recurse *
d2: directory with 2 files
d2/f3: (glob)
>>>
0 base
<<<
d2/f4: (glob)
>>>
0 base
<<<
f1:
>>>
5 second change
<<<
f2:
>>>
6 second change
<<<
The other way around:
$ hg up -C -r5
4 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg merge -v --debug --config merge.preferancestor="*"
note: merging e673248094b1+ and 6373bbfdae1d using bids from ancestors 0f6b37dbe527 and d1d156401c1b
calculating bids for ancestor 0f6b37dbe527
searching for copies back to rev 3
unmatched files in local:
d1/f3
d1/f4
unmatched files in other:
d2/f4
all copies found (* = to merge, ! = divergent, % = renamed and deleted):
src: 'd1/f4' -> dst: 'd2/f4'
checking for directory renames
discovered dir src: 'd1/' -> dst: 'd2/'
pending file src: 'd1/f3' -> dst: 'd2/f3'
pending file src: 'd1/f4' -> dst: 'd2/f4'
resolving manifests
branchmerge: True, force: False, partial: False
ancestor: 0f6b37dbe527, local: e673248094b1+, remote: 6373bbfdae1d
d2/f3: remote directory rename - move from d1/f3 -> dm
d2/f4: remote directory rename, both created -> m
f1: remote unchanged -> k
f2: versions differ -> m
calculating bids for ancestor d1d156401c1b
searching for copies back to rev 3
unmatched files in other:
d2/f4
all copies found (* = to merge, ! = divergent, % = renamed and deleted):
src: 'd1/f4' -> dst: 'd2/f4'
checking for directory renames
discovered dir src: 'd1/' -> dst: 'd2/'
resolving manifests
branchmerge: True, force: False, partial: False
ancestor: d1d156401c1b, local: e673248094b1+, remote: 6373bbfdae1d
d1/f3: other deleted -> r
d1/f4: other deleted -> r
d2/f4: remote created -> g
f1: versions differ -> m
f2: remote is newer -> g
auction for merging merge bids
d1/f3: consensus for r
d1/f4: consensus for r
d2/f3: consensus for dm
d2/f4: picking 'get' action
f1: picking 'keep' action
f2: picking 'get' action
end of auction
d1/f3: other deleted -> r
removing d1/f3
d1/f4: other deleted -> r
removing d1/f4
d2/f4: remote created -> g
getting d2/f4
f2: remote is newer -> g
getting f2
f1: remote unchanged -> k
2 files updated, 0 files merged, 2 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ f --dump --recurse *
d2: directory with 2 files
d2/f3: (glob)
>>>
0 base
<<<
d2/f4: (glob)
>>>
0 base
<<<
f1:
>>>
5 second change
<<<
f2:
>>>
6 second change
<<<
Verify how the output looks and and how verbose it is:
$ hg up -qC
$ hg merge
2 files updated, 0 files merged, 2 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg up -qC tip
$ hg merge -v
note: merging 6373bbfdae1d+ and e673248094b1 using bids from ancestors 0f6b37dbe527 and d1d156401c1b
calculating bids for ancestor 0f6b37dbe527
resolving manifests
calculating bids for ancestor d1d156401c1b
resolving manifests
auction for merging merge bids
d2/f3: consensus for dg
d2/f4: consensus for m
f1: picking 'get' action
f2: picking 'keep' action
end of auction
getting f1
getting d1/f3 to d2/f3
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg up -qC
$ hg merge -v --debug --config merge.preferancestor="*"
note: merging 6373bbfdae1d+ and e673248094b1 using bids from ancestors 0f6b37dbe527 and d1d156401c1b
calculating bids for ancestor 0f6b37dbe527
searching for copies back to rev 3
unmatched files in local:
d2/f4
unmatched files in other:
d1/f3
d1/f4
all copies found (* = to merge, ! = divergent, % = renamed and deleted):
src: 'd1/f4' -> dst: 'd2/f4'
checking for directory renames
discovered dir src: 'd1/' -> dst: 'd2/'
pending file src: 'd1/f3' -> dst: 'd2/f3'
pending file src: 'd1/f4' -> dst: 'd2/f4'
resolving manifests
branchmerge: True, force: False, partial: False
ancestor: 0f6b37dbe527, local: 6373bbfdae1d+, remote: e673248094b1
d2/f3: local directory rename - get from d1/f3 -> dg
d2/f4: local directory rename, both created -> m
f1: remote is newer -> g
f2: versions differ -> m
calculating bids for ancestor d1d156401c1b
searching for copies back to rev 3
unmatched files in local:
d2/f4
all copies found (* = to merge, ! = divergent, % = renamed and deleted):
src: 'd1/f4' -> dst: 'd2/f4'
checking for directory renames
discovered dir src: 'd1/' -> dst: 'd2/'
resolving manifests
branchmerge: True, force: False, partial: False
ancestor: d1d156401c1b, local: 6373bbfdae1d+, remote: e673248094b1
f1: versions differ -> m
f2: remote unchanged -> k
auction for merging merge bids
d2/f3: consensus for dg
d2/f4: consensus for m
f1: picking 'get' action
f2: picking 'keep' action
end of auction
preserving d2/f4 for resolve of d2/f4
f1: remote is newer -> g
getting f1
f2: remote unchanged -> k
d2/f3: local directory rename - get from d1/f3 -> dg
getting d1/f3 to d2/f3
d2/f4: local directory rename, both created -> m (premerge)
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ cd ..
http://stackoverflow.com/questions/9350005/how-do-i-specify-a-merge-base-to-use-in-a-hg-merge/9430810
$ hg init ancestor-merging
$ cd ancestor-merging
$ echo a > x
$ hg commit -A -m a x
$ hg update -q 0
$ echo b >> x
$ hg commit -m b
$ hg update -q 0
$ echo c >> x
$ hg commit -qm c
$ hg update -q 1
$ hg merge -q --tool internal:local 2
$ echo c >> x
$ hg commit -m bc
$ hg update -q 2
$ hg merge -q --tool internal:local 1
$ echo b >> x
$ hg commit -qm cb
$ hg merge --config merge.preferancestor='!'
note: using 70008a2163f6 as ancestor of 0d355fdef312 and 4b8b546a3eef
alternatively, use --config merge.preferancestor=b211bbc6eb3c
merging x
0 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ cat x
a
c
b
c
$ hg up -qC .
$ hg merge --config merge.preferancestor=b211bbc6eb3c
note: using b211bbc6eb3c as ancestor of 0d355fdef312 and 4b8b546a3eef
alternatively, use --config merge.preferancestor=70008a2163f6
merging x
0 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ cat x
a
b
c
b
$ hg up -qC .
$ hg merge -v --config merge.preferancestor="*"
note: merging 0d355fdef312+ and 4b8b546a3eef using bids from ancestors 70008a2163f6 and b211bbc6eb3c
calculating bids for ancestor 70008a2163f6
resolving manifests
calculating bids for ancestor b211bbc6eb3c
resolving manifests
auction for merging merge bids
x: multiple bids for merge action:
versions differ -> m
versions differ -> m
x: ambiguous merge - picked m action
end of auction
merging x
0 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ cat x
a
c
b
c
Verify that the old context ancestor works with / despite preferancestor:
$ hg log -r 'ancestor(head())' --config merge.preferancestor=1 -T '{rev}\n'
1
$ hg log -r 'ancestor(head())' --config merge.preferancestor=2 -T '{rev}\n'
2
$ hg log -r 'ancestor(head())' --config merge.preferancestor=3 -T '{rev}\n'
1
$ hg log -r 'ancestor(head())' --config merge.preferancestor='1337 * - 2' -T '{rev}\n'
2
$ cd ..