obsolete: order of magnitude speedup in _computebumpedset
Reminder: a changeset is said "bumped" if it tries to obsolete a immutable
changeset.
The previous algorithm for computing bumped changeset was:
1) Get all public changesets
2) Find all they successors
3) Search for stuff that are eligible for being "bumped"
(mutable and non obsolete)
The entry size of this algorithm is `O(len(public))` which is mostly the same as
`O(len(repo))`. Even this this approach mean fewer obsolescence marker are
traveled, this is not very scalable.
The new algorithm is:
1) For each potential bumped changesets (non obsolete mutable)
2) iterate over precursors
3) if a precursors is public. changeset is bumped
We travel more obsolescence marker, but the entry size is much smaller since
the amount of potential bumped should remains mostly stable with time `O(1)`.
On some confidential gigantic repo this move bumped computation from 15.19s to
0.46s (×33 speedup…). On "smaller" repo (mercurial, cubicweb's review) no
significant gain were seen. The additional traversal of obsolescence marker is
probably probably counter balance the advantage of it.
Other optimisation could be done in the future (eg: sharing precursors cache
for divergence detection)
$ heads()
> {
> hg heads --template '{rev}: {desc|firstline|strip} ({branches})\n' "$@"
> }
$ hg init a
$ cd a
$ echo 'root' >root
$ hg add root
$ hg commit -m "Adding root node"
$ heads
0: Adding root node ()
-------
$ heads .
0: Adding root node ()
=======
$ echo 'a' >a
$ hg add a
$ hg branch a
marked working directory as branch a
(branches are permanent and global, did you want a bookmark?)
$ hg commit -m "Adding a branch"
$ heads
1: Adding a branch (a)
0: Adding root node ()
-------
$ heads .
1: Adding a branch (a)
=======
$ hg update -C 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo 'b' >b
$ hg add b
$ hg branch b
marked working directory as branch b
(branches are permanent and global, did you want a bookmark?)
$ hg commit -m "Adding b branch"
$ heads
2: Adding b branch (b)
1: Adding a branch (a)
0: Adding root node ()
-------
$ heads .
2: Adding b branch (b)
=======
$ echo 'bh1' >bh1
$ hg add bh1
$ hg commit -m "Adding b branch head 1"
$ heads
3: Adding b branch head 1 (b)
1: Adding a branch (a)
0: Adding root node ()
-------
$ heads .
3: Adding b branch head 1 (b)
=======
$ hg update -C 2
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo 'bh2' >bh2
$ hg add bh2
$ hg commit -m "Adding b branch head 2"
created new head
$ heads
4: Adding b branch head 2 (b)
3: Adding b branch head 1 (b)
1: Adding a branch (a)
0: Adding root node ()
$ heads .
4: Adding b branch head 2 (b)
3: Adding b branch head 1 (b)
=======
$ hg update -C 2
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo 'bh3' >bh3
$ hg add bh3
$ hg commit -m "Adding b branch head 3"
created new head
$ heads
5: Adding b branch head 3 (b)
4: Adding b branch head 2 (b)
3: Adding b branch head 1 (b)
1: Adding a branch (a)
0: Adding root node ()
-------
$ heads .
5: Adding b branch head 3 (b)
4: Adding b branch head 2 (b)
3: Adding b branch head 1 (b)
=======
$ hg merge 4
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg commit -m "Merging b branch head 2 and b branch head 3"
$ heads
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
1: Adding a branch (a)
0: Adding root node ()
-------
$ heads .
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
=======
$ echo 'c' >c
$ hg add c
$ hg branch c
marked working directory as branch c
(branches are permanent and global, did you want a bookmark?)
$ hg commit -m "Adding c branch"
$ heads
7: Adding c branch (c)
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
1: Adding a branch (a)
0: Adding root node ()
-------
$ heads .
7: Adding c branch (c)
=======
$ heads -r 3 .
no open branch heads found on branches c (started at 3)
[1]
$ heads -r 2 .
7: Adding c branch (c)
-------
$ hg update -C 4
0 files updated, 0 files merged, 2 files removed, 0 files unresolved
-------
$ heads -r 3 .
3: Adding b branch head 1 (b)
-------
$ heads -r 2 .
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
-------
$ heads -r 7 .
no open branch heads found on branches b (started at 7)
[1]
=======
$ for i in 0 1 2 3 4 5 6 7; do
> hg update -C "$i"
> heads
> echo '-------'
> heads .
> echo '-------'
> done
0 files updated, 0 files merged, 2 files removed, 0 files unresolved
7: Adding c branch (c)
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
1: Adding a branch (a)
0: Adding root node ()
-------
0: Adding root node ()
-------
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
7: Adding c branch (c)
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
1: Adding a branch (a)
0: Adding root node ()
-------
1: Adding a branch (a)
-------
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
7: Adding c branch (c)
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
1: Adding a branch (a)
0: Adding root node ()
-------
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
-------
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
7: Adding c branch (c)
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
1: Adding a branch (a)
0: Adding root node ()
-------
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
-------
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
7: Adding c branch (c)
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
1: Adding a branch (a)
0: Adding root node ()
-------
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
-------
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
7: Adding c branch (c)
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
1: Adding a branch (a)
0: Adding root node ()
-------
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
-------
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
7: Adding c branch (c)
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
1: Adding a branch (a)
0: Adding root node ()
-------
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
-------
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
7: Adding c branch (c)
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
1: Adding a branch (a)
0: Adding root node ()
-------
7: Adding c branch (c)
-------
=======
$ for i in a b c z; do
> heads "$i"
> echo '-------'
> done
1: Adding a branch (a)
-------
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
-------
7: Adding c branch (c)
-------
abort: unknown revision 'z'!
-------
=======
$ heads 0 1 2 3 4 5 6 7
7: Adding c branch (c)
6: Merging b branch head 2 and b branch head 3 (b)
3: Adding b branch head 1 (b)
1: Adding a branch (a)
0: Adding root node ()
Topological heads:
$ heads -t
7: Adding c branch (c)
3: Adding b branch head 1 (b)
1: Adding a branch (a)
$ cd ..
______________
"created new head" message tests
$ hg init newheadmsg
$ cd newheadmsg
Init: no msg
$ echo 1 > a
$ hg ci -Am "a0: Initial root"
adding a
$ echo 2 >> a
$ hg ci -m "a1 (HN)"
$ hg branch b
marked working directory as branch b
(branches are permanent and global, did you want a bookmark?)
$ echo 1 > b
$ hg ci -Am "b2: Initial root for branch b"
adding b
$ echo 2 >> b
$ hg ci -m "b3 (HN)"
Case NN: msg
$ hg up -q null
$ hg branch -f b
marked working directory as branch b
(branches are permanent and global, did you want a bookmark?)
$ echo 1 > bb
$ hg ci -Am "b4 (NN): new topo root for branch b"
adding bb
created new head
Case HN: no msg
$ echo 2 >> bb
$ hg ci -m "b5 (HN)"
Case BN: msg
$ hg branch -f default
marked working directory as branch default
(branches are permanent and global, did you want a bookmark?)
$ echo 1 > aa
$ hg ci -Am "a6 (BN): new branch root"
adding aa
created new head
Case CN: msg
$ hg up -q 4
$ echo 3 >> bbb
$ hg ci -Am "b7 (CN): regular new head"
adding bbb
created new head
Case BB: msg
$ hg up -q 4
$ hg merge -q 3
$ hg branch -f default
marked working directory as branch default
(branches are permanent and global, did you want a bookmark?)
$ hg ci -m "a8 (BB): weird new branch root"
created new head
Case CB: msg
$ hg up -q 4
$ hg merge -q 1
$ hg ci -m "b9 (CB): new head from branch merge"
created new head
Case HB: no msg
$ hg up -q 7
$ hg merge -q 6
$ hg ci -m "b10 (HB): continuing head from branch merge"
Case CC: msg
$ hg up -q 4
$ hg merge -q 2
$ hg ci -m "b11 (CC): new head from merge"
created new head
Case CH: no msg
$ hg up -q 2
$ hg merge -q 10
$ hg ci -m "b12 (CH): continuing head from merge"
Case HH: no msg
$ hg merge -q 3
$ hg ci -m "b12 (HH): merging two heads"
$ cd ..