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

  $ cat <<EOF >> $HGRCPATH
  > [experimental]
  > evolution = true
  > 
  > [extensions]
  > notify =
  > hooklib =
  > 
  > [phases]
  > publish = False
  > 
  > [notify]
  > sources = pull
  > diffstat = False
  > messageidseed = example
  > domain = example.com
  > 
  > [reposubs]
  > * = baz
  > EOF
  $ hg init a
  $ hg --cwd a debugbuilddag +2
  $ hg init b
  $ cat <<EOF >> b/.hg/hgrc
  > [hooks]
  > incoming.notify = python:hgext.notify.hook
  > txnclose.changeset_obsoleted = python:hgext.hooklib.changeset_obsoleted.hook
  > EOF
  $ hg --cwd b pull ../a | "$PYTHON" $TESTDIR/unwrap-message-id.py
  pulling from ../a
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 0 changes to 0 files
  new changesets 1ea73414a91b:66f7d451a68b (2 drafts)
  MIME-Version: 1.0
  Content-Type: text/plain; charset="us-ascii"
  Content-Transfer-Encoding: 7bit
  Date: * (glob)
  Subject: changeset in * (glob)
  From: debugbuilddag@example.com
  X-Hg-Notification: changeset 1ea73414a91b
  Message-Id: <hg.81c297828fd2d5afaadf2775a6a71b74143b6451dfaac09fac939e9107a50d01@example.com>
  To: baz@example.com
  
  changeset 1ea73414a91b in $TESTTMP/b
  details: $TESTTMP/b?cmd=changeset;node=1ea73414a91b
  description:
  	r0
  MIME-Version: 1.0
  Content-Type: text/plain; charset="us-ascii"
  Content-Transfer-Encoding: 7bit
  Date: * (glob)
  Subject: changeset in * (glob)
  From: debugbuilddag@example.com
  X-Hg-Notification: changeset 66f7d451a68b
  Message-Id: <hg.364d03da7dc13829eb779a805be7e37f54f572e9afcea7d2626856a794d3e8f3@example.com>
  To: baz@example.com
  
  changeset 66f7d451a68b in $TESTTMP/b
  details: $TESTTMP/b?cmd=changeset;node=66f7d451a68b
  description:
  	r1
  (run 'hg update' to get a working copy)
  $ hg --cwd a debugobsolete 1ea73414a91b0920940797d8fc6a11e447f8ea1e
  1 new obsolescence markers
  obsoleted 1 changesets
  1 new orphan changesets
  $ hg --cwd a push ../b --hidden | "$PYTHON" $TESTDIR/unwrap-message-id.py
  1 new orphan changesets
  pushing to ../b
  searching for changes
  no changes found
  1 new obsolescence markers
  obsoleted 1 changesets
  Subject: changeset abandoned
  In-reply-to: <hg.81c297828fd2d5afaadf2775a6a71b74143b6451dfaac09fac939e9107a50d01@example.com>
  Message-Id: <hg.d6329e9481594f0f3c8a84362b3511318bfbce50748ab1123f909eb6fbcab018@example.com>
  Date: * (glob)
  From: test@example.com
  To: baz@example.com
  
  This changeset has been abandoned.

Check that known changesets with known successors do not result in a mail.

  $ hg init c
  $ hg init d
  $ cat <<EOF >> d/.hg/hgrc
  > [hooks]
  > incoming.notify = python:hgext.notify.hook
  > txnclose.changeset_obsoleted = python:hgext.hooklib.changeset_obsoleted.hook
  > EOF
  $ hg --cwd c debugbuilddag '.:parent.*parent'
  $ hg --cwd c push ../d -r 1
  pushing to ../d
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 0 changes to 0 files
  $ hg --cwd c debugobsolete $(hg --cwd c log -T '{node}' -r 1) $(hg --cwd c log -T '{node}' -r 2)
  1 new obsolescence markers
  obsoleted 1 changesets
  $ hg --cwd c push ../d | "$PYTHON" $TESTDIR/unwrap-message-id.py
  pushing to ../d
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 0 changes to 0 files (+1 heads)
  1 new obsolescence markers
  obsoleted 1 changesets