view tests/test-extensions-afterloaded.t @ 47343:9f798c1b0d89 stable

cext: fix memory leak in phases computation

Without this a buffer whose size in bytes is the number of
changesets in the repository is leaked each time the repository is
opened and changeset phases are computed.

Impact: the current code in hgwebdir creates a new `localrepository`
instance for each HTTP request. Since any pull or push is made of several
requests, a team of 100 people can easily produce thousands of such
requests per day.

Being a low-level malloc, this leak can't be seen with the gc module and
tools relying on that, but was spotted by valgrind immediately.

Reproduction
------------

  for i in range(cl_args.iterations):
      repo = hg.repository(baseui, repo_path)
      rev = repo.revs(rev).first()
      ctx = repo[rev]

  del ctx
  del repo
  # avoid any pollution by other type of leak
  # (that should be fixed in 5.8)
  repoview._filteredrepotypes.clear()

  gc.collect()

Measurements
------------

Resident Set Size (RSS), taken on a clone of
mozilla-central for performance analysis (440 000
changesets).

before:
  5.8+hg19.5ac0f2a8ba72  1000 iterations: 1606MB
  5.8+hg19.5ac0f2a8ba72 10000 iterations: 5723MB
after:
  5.8+hg20.e2084d39e145  1000 iterations:  555MB
  5.8+hg20.e2084d39e145 10000 iterations:  555MB
         (double checked, not a copy/paste error)

(e2084d39e14 is the present changeset, before amendment
of the message to add the measurements)

Test the extensions.afterloaded() function

  $ cat > foo.py <<EOF
  > from mercurial import extensions
  > def uisetup(ui):
  >     ui.write(b"foo.uisetup\\n")
  >     ui.flush()
  >     def bar_loaded(loaded):
  >         ui.write(b"foo: bar loaded: %r\\n" % (loaded,))
  >         ui.flush()
  >     extensions.afterloaded(b'bar', bar_loaded)
  > EOF
  $ cat > bar.py <<EOF
  > def uisetup(ui):
  >     ui.write(b"bar.uisetup\\n")
  >     ui.flush()
  > EOF
  $ basepath=`pwd`

  $ hg init basic
  $ cd basic
  $ echo foo > file
  $ hg add file
  $ hg commit -m 'add file'

  $ echo '[extensions]' >> .hg/hgrc
  $ echo "foo = $basepath/foo.py" >> .hg/hgrc
  $ echo "bar = $basepath/bar.py" >> .hg/hgrc
  $ hg log -r. -T'{rev}\n'
  foo.uisetup
  foo: bar loaded: True
  bar.uisetup
  0

Test afterloaded with the opposite extension load order

  $ cd ..
  $ hg init basic_reverse
  $ cd basic_reverse
  $ echo foo > file
  $ hg add file
  $ hg commit -m 'add file'

  $ echo '[extensions]' >> .hg/hgrc
  $ echo "bar = $basepath/bar.py" >> .hg/hgrc
  $ echo "foo = $basepath/foo.py" >> .hg/hgrc
  $ hg log -r. -T'{rev}\n'
  bar.uisetup
  foo.uisetup
  foo: bar loaded: True
  0

Test the extensions.afterloaded() function when the requested extension is not
loaded

  $ cd ..
  $ hg init notloaded
  $ cd notloaded
  $ echo foo > file
  $ hg add file
  $ hg commit -m 'add file'

  $ echo '[extensions]' >> .hg/hgrc
  $ echo "foo = $basepath/foo.py" >> .hg/hgrc
  $ hg log -r. -T'{rev}\n'
  foo.uisetup
  foo: bar loaded: False
  0

Test the extensions.afterloaded() function when the requested extension is not
configured but fails the minimum version check

  $ cd ..
  $ cat > minvers.py <<EOF
  > minimumhgversion = b'9999.9999'
  > def uisetup(ui):
  >     ui.write(b"minvers.uisetup\\n")
  >     ui.flush()
  > EOF
  $ hg init minversion
  $ cd minversion
  $ echo foo > file
  $ hg add file
  $ hg commit -m 'add file'

  $ echo '[extensions]' >> .hg/hgrc
  $ echo "foo = $basepath/foo.py" >> .hg/hgrc
  $ echo "bar = $basepath/minvers.py" >> .hg/hgrc
  $ hg log -r. -T'{rev}\n'
  (third party extension bar requires version 9999.9999 or newer of Mercurial (current: *); disabling) (glob)
  foo.uisetup
  foo: bar loaded: False
  0

Test the extensions.afterloaded() function when the requested extension is not
configured but fails the minimum version check, using the opposite load order
for the two extensions.

  $ cd ..
  $ hg init minversion_reverse
  $ cd minversion_reverse
  $ echo foo > file
  $ hg add file
  $ hg commit -m 'add file'

  $ echo '[extensions]' >> .hg/hgrc
  $ echo "bar = $basepath/minvers.py" >> .hg/hgrc
  $ echo "foo = $basepath/foo.py" >> .hg/hgrc
  $ hg log -r. -T'{rev}\n'
  (third party extension bar requires version 9999.9999 or newer of Mercurial (current: *); disabling) (glob)
  foo.uisetup
  foo: bar loaded: False
  0