phases: rework the logic of _pushdiscoveryphase to bound complexity This rework the various graph traversal in _pushdiscoveryphase to keep the complexity in check. This is done though a couple of things: - first, limiting the space we have to explore, for example, if we are not in publishing push, we don't need to consider remote draft roots that are also draft locally, as there is nothing to be moved there. - avoid unbounded descendant computation, and use the faster "rev between" computation. This provide a massive boost to performance when exchanging with repository with a massive amount of draft, like mozilla-try: ### data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog # benchmark.name = hg.command.push # bin-env-vars.hg.flavor = default # bin-env-vars.hg.py-re2-module = default # benchmark.variants.explicit-rev = all-out-heads # benchmark.variants.issue6528 = disabled # benchmark.variants.protocol = ssh # benchmark.variants.reuse-external-delta-parent = default ## benchmark.variants.revs = any-1-extra-rev before: 20.346590 seconds after: 11.232059 seconds (-38.15%, -7.48 seconds) ## benchmark.variants.revs = any-100-extra-rev before: 24.752051 seconds after: 15.367412 seconds (-37.91%, -9.38 seconds) After this changes, the push operation is still quite too slow. Some of this can be attributed to general phases slowness (reading all the roots from disk for example) and other know slowness (not using persistent-nodemap, branchmap, tags, etc. We are also working on them, but with this series, phase discovery during push no longer showing up in profile and this is a pretty nice and bit low-hanging fruit out of the way. ### (same case as the above) # benchmark.variants.revs = any-1-extra-rev pre-%ln-change: 44.235070 this-changeset: 11.232059 seconds (-74.61%, -33.00 seconds) # benchmark.variants.revs = any-100-extra-rev pre-%ln-change: 49.234697 this-changeset: 15.367412 seconds (-68.79%, -33.87 seconds) Note that with this change, the `hg push` performance is now much closer to the `hg pull` performance, even it still lagging behind a bit. (and the overall performance are still too slow). ### data-env-vars.name = mozilla-try-2023-03-22-ds2-pnm # benchmark.variants.explicit-rev = all-out-heads # benchmark.variants.issue6528 = disabled # benchmark.variants.protocol = ssh # benchmark.variants.pulled-delta-reuse-policy = default # bin-env-vars.hg.flavor = rust ## benchmark.variants.revs = any-1-extra-rev hg.command.pull: 6.517450 hg.command.push: 11.219888 ## benchmark.variants.revs = any-100-extra-rev hg.command.pull: 10.160991 hg.command.push: 14.251107 ### data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog # bin-env-vars.hg.py-re2-module = default # benchmark.variants.explicit-rev = all-out-heads # benchmark.variants.issue6528 = disabled # benchmark.variants.protocol = ssh # benchmark.variants.pulled-delta-reuse-policy = default ## bin-env-vars.hg.flavor = default ## benchmark.variants.revs = any-1-extra-rev hg.command.pull: 8.577772 hg.command.push: 11.232059 ## bin-env-vars.hg.flavor = default ## benchmark.variants.revs = any-100-extra-rev hg.command.pull: 13.152976 hg.command.push: 15.367412 ## bin-env-vars.hg.flavor = rust ## benchmark.variants.revs = any-1-extra-rev hg.command.pull: 8.731982 hg.command.push: 11.178751 ## bin-env-vars.hg.flavor = rust ## benchmark.variants.revs = any-100-extra-rev hg.command.pull: 13.184236 hg.command.push: 15.620843

#require no-windows

  $ . "$TESTDIR/remotefilelog-library.sh"

Set up an extension to make sure remotefilelog clientsetup() runs
unconditionally even if we have never used a local shallow repo.
This mimics behavior when using remotefilelog with chg.  clientsetup() can be
triggered due to a shallow repo, and then the code can later interact with
non-shallow repositories.

  $ cat > setupremotefilelog.py << EOF
  > from mercurial import extensions
  > def extsetup(ui):
  >     remotefilelog = extensions.find(b'remotefilelog')
  >     remotefilelog.onetimeclientsetup(ui)
  > EOF

Set up the master repository to pull from.

  $ hg init master
  $ cd master
  $ cat >> .hg/hgrc <<EOF
  > [remotefilelog]
  > server=True
  > EOF
  $ echo x > x
  $ hg commit -qAm x

  $ cd ..

  $ hg clone ssh://user@dummy/master child -q

We should see the remotefilelog capability here, which advertises that
the server supports our custom getfiles method.

  $ cd master
  $ echo 'hello' | hg -R . serve --stdio | grep capa | identifyrflcaps
  exp-remotefilelog-ssh-getfiles-1
  x_rfl_getfile
  x_rfl_getflogheads
  $ echo 'capabilities' | hg -R . serve --stdio | identifyrflcaps ; echo
  exp-remotefilelog-ssh-getfiles-1
  x_rfl_getfile
  x_rfl_getflogheads
  

Pull to the child repository.  Use our custom setupremotefilelog extension
to ensure that remotefilelog.onetimeclientsetup() gets triggered.  (Without
using chg it normally would not be run in this case since the local repository
is not shallow.)

  $ echo y > y
  $ hg commit -qAm y

  $ cd ../child
  $ hg pull --config extensions.setuprfl=$TESTTMP/setupremotefilelog.py
  pulling from ssh://user@dummy/master
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets d34c38483be9
  (run 'hg update' to get a working copy)

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

  $ cat y
  y

Test that bundle works in a non-remotefilelog repo w/ remotefilelog loaded

  $ echo y >> y
  $ hg commit -qAm "modify y"
  $ hg bundle --base ".^" --rev . mybundle.hg --config extensions.setuprfl=$TESTTMP/setupremotefilelog.py
  1 changesets found

  $ cd ..