bundle: include advisory rev branch cache part in bundle2 bundle
`hg bundle` command producing bundle2 will now include an optional part
containing the revision-branch cache data.
The data sent are mostly nodes so it is quite compact. The goal of the
rev-branch-cache is to speed up branch map computation, especially when the
branchmap gets invalidated so we send data for all exchanged changesets. In
addition, computing the relevant heads to send in case of partial pulling would
be challenging.
As a reminder, the rev branch cache data significantly speed up branch
computation. Having it around provides a small speedup to pull/clone and much
higher tolerance to branch map cache invalidation that might happens from later
commands.
On the Mercurial repository, computing the visible branchmap from scratch move
from 2.00 seconds to 0.34s (a -83% speedup).
Using this new part, Unbundling the full Mercurial repository moves from 25.736
seconds to 24.030 seconds (around -7% speedup). The bundle size increase is
around 3% (from 22.43 MB to 23.13MB)
On an half a million revision repository with twenty thousand
branches, computing the branchmap moves from 75 seconds to 45 second (-40%) if
the caches is used.
A bundle containing 50 000 changesets in such repository get a 0.5% size
increase from such part for a -3% unbundling time speedup.
$ cat >> $HGRCPATH <<EOF
> [experimental]
> bundle-phases=yes
> [extensions]
> strip=
> drawdag=$TESTDIR/drawdag.py
> EOF
Set up repo with linear history
$ hg init linear
$ cd linear
$ hg debugdrawdag <<'EOF'
> E
> |
> D
> |
> C
> |
> B
> |
> A
> EOF
$ hg phase --public A
$ hg phase --force --secret D
$ hg log -G -T '{desc} {phase}\n'
o E secret
|
o D secret
|
o C draft
|
o B draft
|
o A public
Phases are restored when unbundling
$ hg bundle --base B -r E bundle
3 changesets found
$ hg debugbundle bundle
Stream params: {Compression: BZ}
changegroup -- {nbchanges: 3, targetphase: 2, version: 02}
26805aba1e600a82e93661149f2313866a221a7b
f585351a92f85104bff7c284233c338b10eb1df7
9bc730a19041f9ec7cb33c626e811aa233efb18c
cache:rev-branch-cache -- {}
phase-heads -- {}
26805aba1e600a82e93661149f2313866a221a7b draft
$ hg strip --no-backup C
$ hg unbundle -q bundle
$ rm bundle
$ hg log -G -T '{desc} {phase}\n'
o E secret
|
o D secret
|
o C draft
|
o B draft
|
o A public
Root revision's phase is preserved
$ hg bundle -a bundle
5 changesets found
$ hg strip --no-backup A
$ hg unbundle -q bundle
$ rm bundle
$ hg log -G -T '{desc} {phase}\n'
o E secret
|
o D secret
|
o C draft
|
o B draft
|
o A public
Completely public history can be restored
$ hg phase --public E
$ hg bundle -a bundle
5 changesets found
$ hg strip --no-backup A
$ hg unbundle -q bundle
$ rm bundle
$ hg log -G -T '{desc} {phase}\n'
o E public
|
o D public
|
o C public
|
o B public
|
o A public
Direct transition from public to secret can be restored
$ hg phase --secret --force D
$ hg bundle -a bundle
5 changesets found
$ hg strip --no-backup A
$ hg unbundle -q bundle
$ rm bundle
$ hg log -G -T '{desc} {phase}\n'
o E secret
|
o D secret
|
o C public
|
o B public
|
o A public
Revisions within bundle preserve their phase even if parent changes its phase
$ hg phase --draft --force B
$ hg bundle --base B -r E bundle
3 changesets found
$ hg strip --no-backup C
$ hg phase --public B
$ hg unbundle -q bundle
$ rm bundle
$ hg log -G -T '{desc} {phase}\n'
o E secret
|
o D secret
|
o C draft
|
o B public
|
o A public
Phase of ancestors of stripped node get advanced to accommodate child
$ hg bundle --base B -r E bundle
3 changesets found
$ hg strip --no-backup C
$ hg phase --force --secret B
$ hg unbundle -q bundle
$ rm bundle
$ hg log -G -T '{desc} {phase}\n'
o E secret
|
o D secret
|
o C draft
|
o B draft
|
o A public
Unbundling advances phases of changesets even if they were already in the repo.
To test that, create a bundle of everything in draft phase and then unbundle
to see that secret becomes draft, but public remains public.
$ hg phase --draft --force A
$ hg phase --draft E
$ hg bundle -a bundle
5 changesets found
$ hg phase --public A
$ hg phase --secret --force E
$ hg unbundle -q bundle
$ rm bundle
$ hg log -G -T '{desc} {phase}\n'
o E draft
|
o D draft
|
o C draft
|
o B draft
|
o A public
Unbundling change in the middle of a stack does not affect later changes
$ hg strip --no-backup E
$ hg phase --secret --force D
$ hg log -G -T '{desc} {phase}\n'
o D secret
|
o C draft
|
o B draft
|
o A public
$ hg bundle --base A -r B bundle
1 changesets found
$ hg unbundle -q bundle
$ rm bundle
$ hg log -G -T '{desc} {phase}\n'
o D secret
|
o C draft
|
o B draft
|
o A public
$ cd ..
Set up repo with non-linear history
$ hg init non-linear
$ cd non-linear
$ hg debugdrawdag <<'EOF'
> D E
> |\|
> B C
> |/
> A
> EOF
$ hg phase --public C
$ hg phase --force --secret B
$ hg log -G -T '{node|short} {desc} {phase}\n'
o 03ca77807e91 E draft
|
| o 4e4f9194f9f1 D secret
|/|
o | dc0947a82db8 C public
| |
| o 112478962961 B secret
|/
o 426bada5c675 A public
Restore bundle of entire repo
$ hg bundle -a bundle
5 changesets found
$ hg debugbundle bundle
Stream params: {Compression: BZ}
changegroup -- {nbchanges: 5, targetphase: 2, version: 02}
426bada5c67598ca65036d57d9e4b64b0c1ce7a0
112478962961147124edd43549aedd1a335e44bf
dc0947a82db884575bb76ea10ac97b08536bfa03
4e4f9194f9f181c57f62e823e8bdfa46ab9e4ff4
03ca77807e919db8807c3749086dc36fb478cac0
cache:rev-branch-cache -- {}
phase-heads -- {}
dc0947a82db884575bb76ea10ac97b08536bfa03 public
03ca77807e919db8807c3749086dc36fb478cac0 draft
$ hg strip --no-backup A
$ hg unbundle -q bundle
$ rm bundle
$ hg log -G -T '{node|short} {desc} {phase}\n'
o 03ca77807e91 E draft
|
| o 4e4f9194f9f1 D secret
|/|
o | dc0947a82db8 C public
| |
| o 112478962961 B secret
|/
o 426bada5c675 A public
$ hg bundle --base 'A + C' -r D bundle
2 changesets found
$ hg debugbundle bundle
Stream params: {Compression: BZ}
changegroup -- {nbchanges: 2, targetphase: 2, version: 02}
112478962961147124edd43549aedd1a335e44bf
4e4f9194f9f181c57f62e823e8bdfa46ab9e4ff4
cache:rev-branch-cache -- {}
phase-heads -- {}
$ rm bundle
$ hg bundle --base A -r D bundle
3 changesets found
$ hg debugbundle bundle
Stream params: {Compression: BZ}
changegroup -- {nbchanges: 3, targetphase: 2, version: 02}
112478962961147124edd43549aedd1a335e44bf
dc0947a82db884575bb76ea10ac97b08536bfa03
4e4f9194f9f181c57f62e823e8bdfa46ab9e4ff4
cache:rev-branch-cache -- {}
phase-heads -- {}
dc0947a82db884575bb76ea10ac97b08536bfa03 public
$ rm bundle
$ hg bundle --base 'B + C' -r 'D + E' bundle
2 changesets found
$ hg debugbundle bundle
Stream params: {Compression: BZ}
changegroup -- {nbchanges: 2, targetphase: 2, version: 02}
4e4f9194f9f181c57f62e823e8bdfa46ab9e4ff4
03ca77807e919db8807c3749086dc36fb478cac0
cache:rev-branch-cache -- {}
phase-heads -- {}
03ca77807e919db8807c3749086dc36fb478cac0 draft
$ rm bundle