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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  $ . $TESTDIR/wireprotohelpers.sh

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  $ hg init server

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  $ enablehttpv2 server

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  $ cd server

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  $ cat >> .hg/hgrc << EOF

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  > [web]

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  > push_ssl = false

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  > allow-push = *

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  > EOF

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  $ hg debugdrawdag << EOF

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  > C D

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  > |/

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  > B

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  > |

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  > A

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  > EOF

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  $ root_node=$(hg log -r A -T '{node}')

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  $ hg serve -p $HGPORT -d --pid-file hg.pid -E error.log

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  $ cat hg.pid > $DAEMON_PIDS

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lookup for known node works

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  $ sendhttpv2peer << EOF

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  > command lookup

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  >     key $root_node

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  > EOF

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  creating http peer for wire protocol version 2

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  sending lookup command

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  response: b'Bk\xad\xa5\xc6u\x98\xcae\x03mW\xd9\xe4\xb6K\x0c\x1c\xe7\xa0'

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  $ cat error.log