view tests/test-issue660.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)

https://bz.mercurial-scm.org/660 and:
https://bz.mercurial-scm.org/322

  $ hg init
  $ echo a > a
  $ mkdir b
  $ echo b > b/b
  $ hg commit -A -m "a is file, b is dir"
  adding a
  adding b/b

File replaced with directory:

  $ rm a
  $ mkdir a
  $ echo a > a/a

Should fail - would corrupt dirstate:

  $ hg add a/a
  abort: file 'a' in dirstate clashes with 'a/a'
  [255]

Removing shadow:

  $ hg rm --after a

Should succeed - shadow removed:

  $ hg add a/a

Directory replaced with file:

  $ rm -r b
  $ echo b > b

Should fail - would corrupt dirstate:

  $ hg add b
  abort: directory 'b' already in dirstate
  [255]

Removing shadow:

  $ hg rm --after b/b

Should succeed - shadow removed:

  $ hg add b

Look what we got:

  $ hg st
  A a/a
  A b
  R a
  R b/b

Revert reintroducing shadow - should fail:

  $ rm -r a b
  $ hg revert b/b
  abort: file 'b' in dirstate clashes with 'b/b'
  [255]

Revert all - should succeed:

  $ hg revert --all
  forgetting a/a
  forgetting b
  undeleting a
  undeleting b/b

  $ hg st

Issue3423:

  $ hg forget a
  $ echo zed > a
  $ hg revert a
  $ hg st
  ? a.orig
  $ rm a.orig

addremove:

  $ rm -r a b
  $ mkdir a
  $ echo a > a/a
  $ echo b > b

  $ hg addremove -s 0
  removing a
  adding a/a
  adding b
  removing b/b

  $ hg st
  A a/a
  A b
  R a
  R b/b

commit:

  $ hg ci -A -m "a is dir, b is file"
  $ hg st --all
  C a/a
  C b

Long directory replaced with file:

  $ mkdir d
  $ mkdir d/d
  $ echo d > d/d/d
  $ hg commit -A -m "d is long directory"
  adding d/d/d

  $ rm -r d
  $ echo d > d

Should fail - would corrupt dirstate:

  $ hg add d
  abort: directory 'd' already in dirstate
  [255]

Removing shadow:

  $ hg rm --after d/d/d

Should succeed - shadow removed:

  $ hg add d
  $ hg ci -md

Update should work at least with clean working directory:

  $ rm -r a b d
  $ hg up -r 0
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ hg st --all
  C a
  C b/b

  $ rm -r a b
  $ hg up -r 1
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ hg st --all
  C a/a
  C b