view tests/test-obsmarkers-effectflag.t @ 49777:e1953a34c110

bundle: emit full snapshot as is, without doing a redelta

With the new `forced` delta-reused policy, it become important to be able to
send full snapshot where full snapshot are needed. Otherwise, the fallback delta
will simply be used on the client side… creating monstrous delta chain, since
revision that are meant as a reset of delta-chain chain becoming too complex are
simply adding a new full delta-tree on the leaf of another one.

In the `non-forced` cases, client process full snapshot from the bundle
differently from deltas, so client will still try to convert the full snapshot
into a delta if possible. So this will no lead to pathological storage
explosion.

I have considered making this configurable, but the impact seems limited enough
that it does not seems to be worth it. Especially with the current
sparse-revlog format that use "delta-tree" with multiple level snapshots, full
snapshot are much less frequent and not that different from other intermediate
snapshot that we are already sending over the wire anyway.

CPU wise, this will help the bundling side a little as it will not need to
reconstruct revisions and compute deltas. The unbundling side might save a tiny
amount of CPU as it won't need to reconstruct the delta-base to reconstruct the
revision full text. This only slightly visible in some of the benchmarks. And
have no real impact on most of them.

### data-env-vars.name      = pypy-2018-08-01-zstd-sparse-revlog
  # benchmark.name          = perf-bundle
  # benchmark.variants.revs = last-40000
before:          11.467186 seconds
just-emit-full:  11.190576 seconds   (-2.41%)
with-pull-force: 11.041091 seconds   (-3.72%)
  # benchmark.name          = perf-unbundle
  # benchmark.variants.revs = last-40000
before:     16.744862
just-emit-full:: 16.561036 seconds   (-1.10%)
with-pull-force: 16.389344 seconds   (-2.12%)
  # benchmark.name          = pull
  # benchmark.variants.revs = last-40000
before:     26.870569
just-emit-full:  26.391188 seconds   (-1.78%)
with-pull-force: 25.633184 seconds   (-4.60%)


Space wise (so network-wise) the impact is fairly small. When taking compression into
account.

Below are tests the size of `hg bundle --all` for a handful of benchmark repositories
(with bzip, zstd compression and without it)

This show a small increase in the bundle size, but nothing really significant
except maybe for mozilla-try (+12%) that nobody really pulls large chunk of anyway.
Mozilla-try is also the repository that benefit the most for not having to
recompute deltas client size.

### mercurial:
bzip-before:     26 406 342 bytes
bzip-after:      26 691 543 bytes  +1.08%

zstd-before:     27 918 645 bytes
zstd-after:      28 075 896 bytes  +0.56%

none-before:     98 675 601 bytes
none-after:     100 411 237 bytes  +1.76%


### pypy
bzip-before:    201 295 752 bytes
bzip-after:     209 780 282 bytes  +4.21%

zstd-before:    202 974 795 bytes
zstd-after:     205 165 780 bytes  +1.08%

none-before:    871 070 261 bytes
none-after:     993 595 057 bytes +14.07%


### netbeans
bzip-before:    601 314 330 bytes
bzip-after:     614 246 241 bytes  +2.15%

zstd-before:    604 745 136 bytes
zstd-after:     615 497 705 bytes  +1.78%

none-before:  3 338 238 571 bytes
none-after:   3 439 422 535 bytes  +3.03%


### mozilla-central
bzip-before:  1 493 006 921 bytes
bzip-after:   1 549 650 570 bytes  +3.79%

zstd-before:  1 481 910 102 bytes
zstd-after:   1 513 052 415 bytes  +2.10%

none-before:  6 535 929 910 bytes
none-after:   7 010 191 342 bytes  +7.26%


### mozilla-try
bzip-before:  6 583 425 999 bytes
bzip-after:   7 423 536 928 bytes +12.76%

zstd-before:  6 021 009 212 bytes
zstd-after:   6 674 922 420 bytes +10.86%

none-before: 22 954 739 558 bytes
none-after:  26 013 854 771 bytes +13.32%

Test the 'effect-flags' feature

Global setup
============

  $ . $TESTDIR/testlib/obsmarker-common.sh
  $ cat >> $HGRCPATH <<EOF
  > [ui]
  > interactive = true
  > [phases]
  > publish=False
  > [extensions]
  > rebase =
  > [experimental]
  > evolution = all
  > evolution.effect-flags = 1
  > EOF

  $ hg init $TESTTMP/effect-flags
  $ cd $TESTTMP/effect-flags
  $ mkcommit ROOT

amend touching the description only
-----------------------------------

  $ mkcommit A0
  $ hg commit --amend -m "A1"

check result

  $ hg debugobsolete --rev .
  471f378eab4c5e25f6c77f785b27c936efb22874 fdf9bde5129a28d4548fadd3f62b265cdd3b7a2e 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '1', 'operation': 'amend', 'user': 'test'}

amend touching the user only
----------------------------

  $ mkcommit B0
  $ hg commit --amend -u "bob <[e-mail]>"

check result

  $ hg debugobsolete --rev .
  ef4a313b1e0ade55718395d80e6b88c5ccd875eb 5485c92d34330dac9d7a63dc07e1e3373835b964 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '16', 'operation': 'amend', 'user': 'test'}

amend touching the date only
----------------------------

  $ mkcommit B1
  $ hg commit --amend -d "42 0"

check result

  $ hg debugobsolete --rev .
  2ef0680ff45038ac28c9f1ff3644341f54487280 4dd84345082e9e5291c2e6b3f335bbf8bf389378 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '32', 'operation': 'amend', 'user': 'test'}

amend touching the branch only
----------------------------

  $ mkcommit B2
  $ hg branch my-branch
  marked working directory as branch my-branch
  (branches are permanent and global, did you want a bookmark?)
  $ hg commit --amend

check result

  $ hg debugobsolete --rev .
  bd3db8264ceebf1966319f5df3be7aac6acd1a8e 14a01456e0574f0e0a0b15b2345486a6364a8d79 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '64', 'operation': 'amend', 'user': 'test'}

  $ hg up default
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved

rebase (parents change)
-----------------------

  $ mkcommit C0
  $ mkcommit D0
  $ hg rebase -r . -d 'desc(B0)'
  rebasing 10:c85eff83a034 tip "D0"

check result

  $ hg debugobsolete --rev .
  c85eff83a0340efd9da52b806a94c350222f3371 da86aa2f19a30d6686b15cae15c7b6c908ec9699 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '4', 'operation': 'rebase', 'user': 'test'}

amend touching the diff
-----------------------

  $ mkcommit E0
  $ echo 42 >> E0
  $ hg commit --amend

check result

  $ hg debugobsolete --rev .
  ebfe0333e0d96f68a917afd97c0a0af87f1c3b5f 75781fdbdbf58a987516b00c980bccda1e9ae588 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '8', 'operation': 'amend', 'user': 'test'}

amend with multiple effect (desc and meta)
-------------------------------------------

  $ mkcommit F0
  $ hg branch my-other-branch
  marked working directory as branch my-other-branch
  $ hg commit --amend -m F1 -u "bob <[e-mail]>" -d "42 0"

check result

  $ hg debugobsolete --rev .
  fad47e5bd78e6aa4db1b5a0a1751bc12563655ff a94e0fd5f1c81d969381a76eb0d37ce499a44fae 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '113', 'operation': 'amend', 'user': 'test'}

rebase not touching the diff
----------------------------

  $ cat << EOF > H0
  > 0
  > 1
  > 2
  > 3
  > 4
  > 5
  > 6
  > 7
  > 8
  > 9
  > 10
  > EOF
  $ hg add H0
  $ hg commit -m 'H0'
  $ echo "H1" >> H0
  $ hg commit -m "H1"
  $ hg up -r "desc(H0)"
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cat << EOF > H0
  > H2
  > 0
  > 1
  > 2
  > 3
  > 4
  > 5
  > 6
  > 7
  > 8
  > 9
  > 10
  > EOF
  $ hg commit -m "H2"
  created new head
  $ hg rebase -s "desc(H1)" -d "desc(H2)" -t :merge3
  rebasing 17:b57fed8d8322 "H1"
  merging H0
  $ hg debugobsolete -r tip
  b57fed8d83228a8ae3748d8c3760a77638dd4f8c e509e2eb3df5d131ff7c02350bf2a9edd0c09478 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '4', 'operation': 'rebase', 'user': 'test'}

amend closing the branch should be detected as meta change
----------------------------------------------------------

  $ hg branch closedbranch
  marked working directory as branch closedbranch
  $ mkcommit G0
  $ mkcommit I0
  $ hg commit --amend --close-branch

check result

  $ hg debugobsolete -r .
  2f599e54c1c6974299065cdf54e1ad640bfb7b5d 12c6238b5e371eea00fd2013b12edce3f070928b 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '2', 'operation': 'amend', 'user': 'test'}