view CONTRIBUTORS @ 51977:42a116f1cdc1

branchmap-v3: introduce a "stop_rev" argument to `headsrevs`

The `headsrevs` method of the revlog already have a `revs` argument to compute
the headrevs of a limited set of heads. However, it disable the use of the
native compiled code to compute the heads, which slows down the branchmap v3
code a lot.

The branchmap v3 usage is actually quite constrained as we will always only
ignores a part at the top of the graph. So we could be significantly faster.

We start by making small change to the python side to improve the situation and
introduce the new API. More collaboration with the native code are coming later.

This massively speedup operation and close most of the remaining gaps between
branchmap-v3 and branchmap-v2. especially on repository with many revs like
mozilla-try. A small overhead remains mostly because the `headrevs` logic
currently has some inefficiently. We will look into them from there.

### benchmark.name                                 = hg.command.unbundle
  # bin-env-vars.hg.py-re2-module                  = default
  # benchmark.variants.issue6528                   = disabled
  # benchmark.variants.resource-usage              = default
  # benchmark.variants.reuse-external-delta-parent = yes
  # benchmark.variants.revs                        = any-1-extra-rev
  # benchmark.variants.source                      = unbundle
  # benchmark.variants.validate                    = default
  # benchmark.variants.verbosity                   = quiet

 ## data-env-vars.name                             = netbeans-2018-08-01-zstd-sparse-revlog
  # bin-env-vars.hg.flavor                         = default
branch-v2:        0.233711  ~~~~~
branch-v3 before: 0.368769  (+57.79%, +0.14)
branch-v3 after:  0.239857   (+2.63%, +0.01)
  # bin-env-vars.hg.flavor                         = rust
branch-v2:        0.235230  ~~~~~
branch-v3 before: 0.372460  (+58.34%, +0.14)
branch-v3 after:  0.240972   (+2.44%, +0.01)
 ## data-env-vars.name                             = netbeans-2018-08-01-ds2-pnm
  # bin-env-vars.hg.flavor                         = rust
branch-v2:        0.255586  ~~~~~
branch-v3 before: 0.318907  (+24.78%, +0.06)
branch-v3 after:  0.268560   (+5.08%, +0.01)

 ## data-env-vars.name                             = mozilla-central-2024-03-22-zstd-sparse-revlog
  # bin-env-vars.hg.flavor                         = default
branch-v2:        0.339010  ~~~~~
branch-v3 before: 0.349752   (+3.17%, +0.01)
branch-v3 after:  0.349389   (+3.06%, +0.01)
  # bin-env-vars.hg.flavor                         = rust
branch-v2:        0.346525  ~~~~~
branch-v3 before: 0.354300   (+2.24%, +0.01)
branch-v3 after:  0.355661   (+2.64%, +0.01)
 ## data-env-vars.name                             = mozilla-central-2024-03-22-ds2-pnm
  # bin-env-vars.hg.flavor                         = rust
branch-v2:        0.380202  ~~~~~
branch-v3 before: 0.396293   (+4.23%, +0.02)
branch-v3 after:  0.408851   (+7.54%, +0.03)

 ## data-env-vars.name                             = mozilla-unified-2024-03-22-zstd-sparse-revlog
  # bin-env-vars.hg.flavor                         = default
branch-v2:        0.412165  ~~~~~
branch-v3 before: 0.424769   (+3.06%, +0.01)
branch-v3 after:  0.427782   (+3.79%, +0.02)
  # bin-env-vars.hg.flavor                         = rust
branch-v2:        0.412397  ~~~~~
branch-v3 before: 0.421796   (+2.28%, +0.01)
branch-v3 after:  0.422354   (+2.41%, +0.01)
 ## data-env-vars.name                             = mozilla-unified-2024-03-22-ds2-pnm
  # bin-env-vars.hg.flavor                         = rust
branch-v2:        0.429501  ~~~~~
branch-v3 before: 0.443849   (+3.34%, +0.01)
branch-v3 after:  0.443197   (+3.19%, +0.01)

 ## data-env-vars.name                             = mozilla-try-2024-03-26-zstd-sparse-revlog
  # bin-env-vars.hg.flavor                         = default
branch-v2:        3.403171  ~~~~~
branch-v3 before: 6.234055  (+83.18%, +2.83)
branch-v3 after:  3.819477  (+12.23%, +0.42)
  # bin-env-vars.hg.flavor                         = rust
branch-v2:        3.454876  ~~~~~
branch-v3 before: 6.307813  (+82.58%, +2.85)
branch-v3 after:  3.590284   (+3.92%, +0.14)
 ## data-env-vars.name                             = mozilla-try-2024-03-26-ds2-pnm
  # bin-env-vars.hg.flavor                         = rust
branch-v2:        3.465435  ~~~~~
branch-v3 before: 5.176076  (+49.36%, +1.71)
branch-v3 after:  3.633278   (+4.84%, +0.17)

[This file is here for historical purposes, all recent contributors
should appear in the changelog directly]

Andrea Arcangeli <andrea at suse.de>
Thomas Arendsen Hein <thomas at intevation.de>
Goffredo Baroncelli <kreijack at libero.it>
Muli Ben-Yehuda <mulix at mulix.org>
Mikael Berthe <mikael at lilotux.net>
Benoit Boissinot <bboissin at gmail.com>
Brendan Cully <brendan at kublai.com>
Vincent Danjean <vdanjean.ml at free.fr>
Jake Edge <jake at edge2.net>
Michael Fetterman <michael.fetterman at intel.com>
Edouard Gomez <ed.gomez at free.fr>
Eric Hopper <hopper at omnifarious.org>
Alecs King <alecsk at gmail.com>
Volker Kleinfeld <Volker.Kleinfeld at gmx.de>
Vadim Lebedev <vadim at mbdsys.com>
Christopher Li <hg at chrisli.org>
Chris Mason <mason at suse.com>
Colin McMillen <mcmillen at cs.cmu.edu>
Wojciech Milkowski <wmilkowski at interia.pl>
Chad Netzer <chad.netzer at gmail.com>
Bryan O'Sullivan <bos at serpentine.com>
Vicent Seguí Pascual <vseguip at gmail.com>
Sean Perry <shaleh at speakeasy.net>
Nguyen Anh Quynh <aquynh at gmail.com>
Ollivier Robert <roberto at keltia.freenix.fr>
Alexander Schremmer <alex at alexanderweb.de>
Arun Sharma <arun at sharma-home.net>
Josef "Jeff" Sipek <jeffpc at optonline.net>
Kevin Smith <yarcs at qualitycode.com>
TK Soh <teekaysoh at yahoo.com>
Radoslaw Szkodzinski <astralstorm at gorzow.mm.pl>
Samuel Tardieu <sam at rfc1149.net>
K Thananchayan <thananck at yahoo.com>
Andrew Thompson <andrewkt at aktzero.com>
Michael S. Tsirkin <mst at mellanox.co.il>
Rafael Villar Burke <pachi at mmn-arquitectos.com>
Tristan Wibberley <tristan at wibberley.org>
Mark Williamson <mark.williamson at cl.cam.ac.uk>