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

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====================================

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Testing head checking code: Case A-4

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====================================

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Mercurial checks for the introduction of new heads on push. Evolution comes

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into play to detect if existing branches on the server are being replaced by

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some of the new one we push.

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This case is part of a series of tests checking this behavior.

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Category A: simple case involving a branch being superseded by another.

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TestCase 4: New changeset as children of the successor

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.. old-state:

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..

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.. * 1-changeset branch

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..

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.. new-state:

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..

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.. * 2-changeset branch, first is a successor, but head is new

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..

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.. expected-result:

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..

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.. * push allowed

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..

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.. graph-summary:

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..

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..       ◔ B

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..       |

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..   A ø⇠◔ A'

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..     |/

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..     ●

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  $ . $TESTDIR/testlib/push-checkheads-util.sh

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Test setup

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----------

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  $ mkdir A4

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  $ cd A4

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  $ setuprepos

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  creating basic server and client repo

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  updating to branch default

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  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

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  $ cd client

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  $ hg up 0

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  0 files updated, 0 files merged, 1 files removed, 0 files unresolved

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  $ mkcommit A1

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  created new head

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  $ hg debugobsolete `getid "desc(A0)" ` `getid "desc(A1)"`

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  1 new obsolescence markers

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  obsoleted 1 changesets

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  $ mkcommit B0

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  $ hg log -G --hidden

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  @  f40ded968333 (draft): B0

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  |

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  o  f6082bc4ffef (draft): A1

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  |

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  | x  8aaa48160adc (draft): A0

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  |/

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  o  1e4be0697311 (public): root

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Actual testing

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--------------

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  $ hg push

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  pushing to $TESTTMP/A4/server

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  searching for changes

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  adding changesets

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  adding manifests

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  adding file changes

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  added 2 changesets with 2 changes to 2 files (+1 heads)

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  1 new obsolescence markers

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  obsoleted 1 changesets

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  $ cd ../../