branchcache: add a "pure topological head" fast path
In a narrow but actually quick common case, all topological heads are all on
the same branch and all open. In this case, computing the branch map is very
simple. We can quickly detect situation where this situation will not change.
So we update the V3 format to be able to express this situation and upgrade the
update code to detect we remains in that mode.
The branch cache is populated with the actual value when the branch map is
accessed, but the update_disk method can do the update without needing to
populate it.
#require cvs no-root
This is https://bz.mercurial-scm.org/1148
and https://bz.mercurial-scm.org/1447
$ cvscall()
> {
> cvs -f "$@" > /dev/null
> }
$ cat <<EOF >> $HGRCPATH
> [extensions]
> convert =
> [convert]
> cvsps.cache = 0
> EOF
create cvs repository
$ mkdir cvsrepo
$ cd cvsrepo
$ CVSROOT=`pwd`
$ export CVSROOT
$ CVS_OPTIONS=-f
$ export CVS_OPTIONS
$ cd ..
$ rmdir cvsrepo
$ cvscall -q -d "$CVSROOT" init
Create a new project
$ mkdir src
$ cd src
$ echo "1" > a
$ echo "1" > b
$ cvscall import -m "init" src v0 r0 | sort
$ cd ..
$ cvscall co src
cvs checkout: Updating src
$ cd src
Branch the project
$ cvscall tag -b BRANCH
cvs tag: Tagging .
$ cvscall up -r BRANCH > /dev/null
cvs update: Updating .
Modify file a, then b, then a
$ sleep 1
$ echo "2" > a
$ cvscall ci -m "mod a"
cvs commit: Examining .
$ echo "2" > b
$ cvscall ci -m "mod b"
cvs commit: Examining .
$ sleep 1
$ echo "3" > a
$ cvscall ci -m "mod a again"
cvs commit: Examining .
Convert
$ cd ..
$ hg convert src
assuming destination src-hg
initializing destination src-hg repository
connecting to $TESTTMP/cvsrepo
scanning source...
collecting CVS rlog
7 log entries
creating changesets
5 changeset entries
sorting...
converting...
4 Initial revision
3 init
2 mod a
1 mod b
0 mod a again
updating tags
Check the result
$ hg -R src-hg log -G --template '{rev} ({branches}) {desc} files: {files}\n'
o 5 () update tags files: .hgtags
|
| o 4 (BRANCH) mod a again files: a
| |
| o 3 (BRANCH) mod b files: b
| |
| o 2 (BRANCH) mod a files: a
| |
| o 1 (v0) init files:
|/
o 0 () Initial revision files: a b
issue 1447
$ cvscall()
> {
> cvs -f "$@" > /dev/null
> sleep 1
> }
$ cvsci()
> {
> cvs -f ci "$@" >/dev/null
> sleep 1
> }
$ cvscall -Q -d `pwd`/cvsmaster2 init
$ cd cvsmaster2
$ CVSROOT=`pwd`
$ export CVSROOT
$ mkdir foo
$ cd ..
$ cvscall -Q co -d cvswork2 foo
$ cd cvswork2
$ echo foo > a.txt
$ echo bar > b.txt
$ cvscall -Q add a.txt b.txt
$ cvsci -m "Initial commit"
cvs commit: Examining .
$ echo foo > b.txt
$ cvsci -m "Fix b on HEAD"
cvs commit: Examining .
$ echo bar > a.txt
$ cvsci -m "Small fix in a on HEAD"
cvs commit: Examining .
$ cvscall -Q tag -b BRANCH
$ cvscall -Q up -P -rBRANCH
$ echo baz > b.txt
$ cvsci -m "Change on BRANCH in b"
cvs commit: Examining .
$ hg debugcvsps -x --parents foo
collecting CVS rlog
5 log entries
creating changesets
4 changeset entries
---------------------
PatchSet 1
Date: * (glob)
Author: * (glob)
Branch: HEAD
Tag: (none)
Log:
Initial commit
Members:
a.txt:INITIAL->1.1
b.txt:INITIAL->1.1
---------------------
PatchSet 2
Date: * (glob)
Author: * (glob)
Branch: HEAD
Tag: (none)
Branchpoints: BRANCH
Parent: 1
Log:
Fix b on HEAD
Members:
b.txt:1.1->1.2
---------------------
PatchSet 3
Date: * (glob)
Author: * (glob)
Branch: HEAD
Tag: (none)
Branchpoints: BRANCH
Parent: 2
Log:
Small fix in a on HEAD
Members:
a.txt:1.1->1.2
---------------------
PatchSet 4
Date: * (glob)
Author: * (glob)
Branch: BRANCH
Tag: (none)
Parent: 3
Log:
Change on BRANCH in b
Members:
b.txt:1.2->1.2.2.1
$ cd ..