view tests/test-subrepo-relative-path.t @ 42743:8c9a6adec67a

rust-discovery: using the children cache in add_missing

The DAG range computation often needs to get back to very old
revisions, and turns out to be disproportionately long, given
that the end goal is to remove the descendents of the given
missing revisons from the undecided set.

The fast iteration capabilities available in the Rust case make
it possible to avoid the DAG range entirely, at the cost of
precomputing the children cache, and to simply iterate on
children of the given missing revisions.

This is a case where staying on the same side of the interface
between the two languages has clear benefits.

On discoveries with initial undecided sets
small enough to bypass sampling entirely, the total cost of
computing the children cache and the subsequent iteration
becomes better than the Python + C counterpart, which relies on
reachableroots2.

For example, on a repo with more than one million revisions with
an initial undecided set of 11 elements, we get these figures:

Rust version with simple iteration
  addcommons: 57.287us
  first undecided computation: 184.278334ms
  first children cache computation: 131.056us
  addmissings iteration: 42.766us
  first addinfo total: 185.24 ms

Python + C version
  first addcommons: 0.29 ms
  addcommons 0.21 ms
  first undecided computation 191.35 ms
  addmissings 45.75 ms
  first addinfo total: 237.77 ms

On discoveries with large undecided sets, the initial price paid
makes the first addinfo slower than the Python + C version,
but that's more than compensated by the gain in sampling and
subsequent iterations.
Here's an extreme example with an undecided set of a million revisions:

Rust version:
  first undecided computation: 293.842629ms
  first children cache computation: 407.911297ms
  addmissings iteration: 34.312869ms
  first addinfo total: 776.02 ms
  taking initial sample
  query 2: sampling time: 1318.38 ms
  query 2; still undecided: 1005013, sample size is: 200
  addmissings: 143.062us

Python + C version:
  first undecided computation 298.13 ms
  addmissings 80.13 ms
  first addinfo total: 399.62 ms
  taking initial sample
  query 2: sampling time: 3957.23 ms
  query 2; still undecided: 1005013, sample size is: 200
  addmissings 52.88 ms

Differential Revision: https://phab.mercurial-scm.org/D6428

Preparing the subrepository 'sub'

  $ hg init sub
  $ echo sub > sub/sub
  $ hg add -R sub
  adding sub/sub
  $ hg commit -R sub -m "sub import"

Preparing the 'main' repo which depends on the subrepo 'sub'

  $ hg init main
  $ echo main > main/main
  $ echo "sub = ../sub" > main/.hgsub
  $ hg clone sub main/sub
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg add -R main
  adding main/.hgsub
  adding main/main
  $ hg commit -R main -m "main import"

Cleaning both repositories, just as a clone -U

  $ hg up -C -R sub null
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg up -C -R main null
  0 files updated, 0 files merged, 3 files removed, 0 files unresolved
  $ rm -rf main/sub

hide outer repo
  $ hg init

Serving them both using hgweb

  $ printf '[paths]\n/main = main\nsub = sub\n' > webdir.conf
  $ hg serve --webdir-conf webdir.conf -a localhost -p $HGPORT \
  >    -A /dev/null -E /dev/null --pid-file hg.pid -d
  $ cat hg.pid >> $DAEMON_PIDS

Clone main from hgweb

  $ hg clone "http://user:pass@localhost:$HGPORT/main" cloned
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 3 changes to 3 files
  new changesets fdfeeb3e979e
  updating to branch default
  cloning subrepo sub from http://user@localhost:$HGPORT/sub
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets 863c1745b441
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved

Ensure that subrepos pay attention to default:pushurl

  $ cat > cloned/.hg/hgrc << EOF
  > [paths]
  > default:pushurl = http://user:pass@localhost:$HGPORT/main
  > EOF

  $ hg -R cloned out -S --config paths.default=bogus://invalid
  comparing with http://user:***@localhost:$HGPORT/main
  searching for changes
  no changes found
  comparing with http://user:***@localhost:$HGPORT/sub
  searching for changes
  no changes found
  [1]

TODO: Figure out why, if the password is left out of the default:pushurl URL,
this says "no changes made to subrepo sub since last push".  It looks like from
the original clone command above, the password is getting stripped off, not
just masked out, and that would make the hashed URL different.

  $ hg -R cloned push --config paths.default=bogus://invalid
  pushing to http://user:***@localhost:$HGPORT/main
  pushing subrepo sub to http://user:***@localhost:$HGPORT/sub
  searching for changes
  no changes found
  searching for changes
  no changes found
  abort: HTTP Error 403: ssl required
  [255]

Checking cloned repo ids

  $ hg id -R cloned
  fdfeeb3e979e tip
  $ hg id -R cloned/sub
  863c1745b441 tip

subrepo debug for 'main' clone

  $ hg debugsub -R cloned
  path sub
   source   ../sub
   revision 863c1745b441bd97a8c4a096e87793073f4fb215

Test sharing with a remote URL reference

  $ hg init absolute_subrepo
  $ cd absolute_subrepo
  $ echo foo > foo.txt
  $ hg ci -Am 'initial commit'
  adding foo.txt
  $ echo "sub = http://localhost:$HGPORT/sub" > .hgsub
  $ hg ci -Am 'add absolute subrepo'
  adding .hgsub
  $ cd ..

Clone pooling works for local clones with a remote subrepo reference.  The
subrepo is cloned to the pool and shared from there, so that all clones will
share the same subrepo.

  $ hg --config extensions.share= --config share.pool=$TESTTMP/pool \
  >    clone absolute_subrepo cloned_from_abs
  (sharing from new pooled repository 8d6a2f1e993b34b6557de0042cfe825ae12a8dae)
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 3 changes to 3 files
  new changesets 8d6a2f1e993b:* (glob)
  searching for changes
  no changes found
  updating working directory
  cloning subrepo sub from http://localhost:$HGPORT/sub
  (sharing from new pooled repository 863c1745b441bd97a8c4a096e87793073f4fb215)
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets 863c1745b441
  searching for changes
  no changes found
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved

Vanilla sharing with a subrepo remote path reference will clone the subrepo.
Each share of these top level repos will end up with independent subrepo copies
(potentially leaving the shared parent with dangling cset references).

  $ hg --config extensions.share= share absolute_subrepo shared_from_abs
  updating working directory
  cloning subrepo sub from http://localhost:$HGPORT/sub
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets 863c1745b441
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ hg --config extensions.share= share -U absolute_subrepo shared_from_abs2
  $ hg -R shared_from_abs2 update -r tip
  cloning subrepo sub from http://localhost:$HGPORT/sub
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets 863c1745b441
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved

A parent repo without its subrepo available locally can be shared if the
subrepo is referenced by absolute path.

  $ hg clone -U absolute_subrepo cloned_null_from_abs
  $ hg --config extensions.share= share cloned_null_from_abs shared_from_null_abs
  updating working directory
  cloning subrepo sub from http://localhost:$HGPORT/sub
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets 863c1745b441
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ killdaemons.py

subrepo paths with ssh urls

  $ hg clone -e "\"$PYTHON\" \"$TESTDIR/dummyssh\"" ssh://user@dummy/cloned sshclone
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 3 changes to 3 files
  new changesets fdfeeb3e979e
  updating to branch default
  cloning subrepo sub from ssh://user@dummy/sub
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets 863c1745b441
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ hg -R sshclone push -e "\"$PYTHON\" \"$TESTDIR/dummyssh\"" ssh://user@dummy/`pwd`/cloned
  pushing to ssh://user@dummy/$TESTTMP/cloned
  pushing subrepo sub to ssh://user@dummy/$TESTTMP/sub
  searching for changes
  no changes found
  searching for changes
  no changes found
  [1]

  $ cat dummylog
  Got arguments 1:user@dummy 2:hg -R cloned serve --stdio
  Got arguments 1:user@dummy 2:hg -R sub serve --stdio
  Got arguments 1:user@dummy 2:hg -R $TESTTMP/cloned serve --stdio
  Got arguments 1:user@dummy 2:hg -R $TESTTMP/sub serve --stdio