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)

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#require bzr

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  $ . "$TESTDIR/bzr-definitions"

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  $ cat > treeset.py <<EOF

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  > import sys

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  > from bzrlib import workingtree

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  > wt = workingtree.WorkingTree.open('.')

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  > 

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  > message, rootid = sys.argv[1:]

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  > wt.set_root_id('tree_root-%s' % rootid)

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  > wt.commit(message)

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  > EOF

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change the id of the tree root

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  $ mkdir test-change-treeroot-id

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  $ cd test-change-treeroot-id

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  $ bzr init -q source

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  $ cd source

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  $ echo content > file

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  $ bzr add -q file

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  $ bzr commit -q -m 'Initial add'

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  $ "$PYTHON" ../../treeset.py 'Changed root' new

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  $ cd ..

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  $ hg convert source source-hg

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  initializing destination source-hg repository

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  scanning source...

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  sorting...

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  converting...

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  1 Initial add

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  0 Changed root

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  $ manifest source-hg tip

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  % manifest of tip

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  644   file

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  $ cd ..