annotate tests/test-simple-update.t @ 52060:8b7123c8947b

update: add a Rust fast-path when updating from null (and clean)

This case is easy to detect and we have all we need to generate a valid
working copy and dirstate entirely in Rust, which speeds things up
considerably:

On my machine updating a repo of ~300k files goes from 10.00s down to 4.2s,
all while consuming 50% less system time, with all caches hot.
Something to note is that further improvements will probably happen
with the upcoming `InnerRevlog` series that does smarter
mmap hanlding, especially for filelogs.

Here are benchmark numbers on a machine with only 4 cores (and no SMT enabled)

```
### data-env-vars.name               = heptapod-public-2024-03-25-ds2-pnm
  # benchmark.name                   = hg.command.update
  # bin-env-vars.hg.py-re2-module    = default
  # bin-env-vars.hg.changeset.node   = <this change>
  # benchmark.variants.atomic-update = no
  # benchmark.variants.scenario      = null-to-tip
  # benchmark.variants.worker        = default
default: 5.328762  ~~~~~
rust: 1.308654  (-75.44%, -4.02)
### data-env-vars.name               = mercurial-devel-2024-03-22-ds2-pnm
  # benchmark.name                   = hg.command.update
  # bin-env-vars.hg.py-re2-module    = default
  # bin-env-vars.hg.changeset.node   = <this change>
  # benchmark.variants.atomic-update = no
  # benchmark.variants.scenario      = null-to-tip
  # benchmark.variants.worker        = default
default: 1.693271  ~~~~~
rust: 1.151053  (-32.02%, -0.54)
### data-env-vars.name               = mozilla-unified-2024-03-22-ds2-pnm
  # benchmark.name                   = hg.command.update
  # bin-env-vars.hg.py-re2-module    = default
  # bin-env-vars.hg.changeset.node   = <this change>
  # benchmark.variants.atomic-update = no
  # benchmark.variants.scenario      = null-to-tip
  # benchmark.variants.worker        = default
default: 38.901613  ~~~~~
rust: 11.637880 (-70.08%, -27.26)
### data-env-vars.name               = netbsd-xsrc-public-2024-09-19-ds2-pnm
  # benchmark.name                   = hg.command.update
  # bin-env-vars.hg.py-re2-module    = default
  # bin-env-vars.hg.changeset.node   = <this change>
  # benchmark.variants.atomic-update = no
  # benchmark.variants.scenario      = null-to-tip
  # benchmark.variants.worker        = default
default: 4.793727  ~~~~~
rust: 1.505905  (-68.59%, -3.29)
```

  $ hg init test
  $ cd test
  $ echo foo>foo
  $ hg addremove
  adding foo
  $ hg commit -m "1"

  $ hg verify -q

  $ hg clone . ../branch
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd ../branch
  $ hg co
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo bar>>foo
  $ hg commit -m "2" -d '1 0'

  $ cd ../test

  $ hg pull ../branch
  pulling from ../branch
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets 84b9316f7b31
  1 local changesets published
  (run 'hg update' to get a working copy)

  $ hg verify -q

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

  $ cat foo
  foo
  bar

  $ hg manifest --debug
  6f4310b00b9a147241b071a60c28a650827fb03d 644   foo

update to rev 0 with a date

  $ hg upd -d foo 0
  abort: you can't specify a revision and a date
  [10]

update by date

  $ hg update -d '<1970-01-01 00:00:02 +0000'
  found revision 1 from Thu Jan 01 00:00:01 1970 +0000
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg update -d '<1970-01-01 00:00:01 +0000'
  found revision 1 from Thu Jan 01 00:00:01 1970 +0000
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg update -d '<1970-01-01 00:00:00 +0000'
  found revision 0 from Thu Jan 01 00:00:00 1970 +0000
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ hg update -d '>1970-01-01 00:00:02 +0000'
  abort: revision matching date not found
  [10]
  $ hg update -d '>1970-01-01 00:00:01 +0000'
  found revision 1 from Thu Jan 01 00:00:01 1970 +0000
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg update -d '>1970-01-01 00:00:00 +0000'
  found revision 1 from Thu Jan 01 00:00:01 1970 +0000
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved

update to default destination (with empty revspec)

  $ hg update -q null
  $ hg update
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg id
  84b9316f7b31 tip

  $ hg update -q null
  $ hg update -r ''
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg id
  84b9316f7b31 tip

  $ hg update -q null
  $ hg update ''
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg id
  84b9316f7b31 tip

  $ cd ..

update with worker processes

#if no-windows

  $ cat <<EOF > forceworker.py
  > from mercurial import extensions, merge, worker
  > def nocost(orig, ui, costperop, nops, threadsafe=True):
  >     return worker._numworkers(ui) > 1
  > def uisetup(ui):
  >     extensions.wrapfunction(worker, 'worthwhile', nocost)
  >     merge.MAYBE_USE_RUST_UPDATE = False
  > EOF

  $ hg init worker
  $ cd worker
  $ cat <<EOF >> .hg/hgrc
  > [extensions]
  > forceworker = $TESTTMP/forceworker.py
  > [worker]
  > numcpus = 4
  > EOF
  $ for i in `"$PYTHON" $TESTDIR/seq.py 1 100`; do
  >   echo $i > $i
  > done
  $ hg ci -qAm 'add 100 files'

  $ hg update null
  0 files updated, 0 files merged, 100 files removed, 0 files unresolved
  $ hg update -v | grep 100
  getting 100
  100 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg status

  $ cd ..

#endif