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 wire protocol unbundle with hashed heads (capability: unbundlehash)
$ cat << EOF >> $HGRCPATH
> [devel]
> # This tests is intended for bundle1 only.
> # bundle2 carries the head information inside the bundle itself and
> # always uses 'force' as the heads value.
> legacy.exchange = bundle1
> EOF
Create a remote repository.
$ hg init remote
$ hg serve -R remote --config web.push_ssl=False --config web.allow_push=* -p $HGPORT -d --pid-file=hg1.pid -E error.log -A access.log
$ cat hg1.pid >> $DAEMON_PIDS
Clone the repository and push a change.
$ hg clone http://localhost:$HGPORT/ local
no changes found
updating to branch default
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ touch local/README
$ hg ci -R local -A -m hoge
adding README
$ hg push -R local
pushing to http://localhost:$HGPORT/
searching for changes
remote: adding changesets
remote: adding manifests
remote: adding file changes
remote: added 1 changesets with 1 changes to 1 files
Ensure hashed heads format is used.
The hash here is always the same since the remote repository only has the null head.
$ cat access.log | grep unbundle
* - - [*] "POST /?cmd=unbundle HTTP/1.1" 200 - x-hgarg-1:heads=686173686564+6768033e216468247bd031a0a2d9876d79818f8f* (glob)
Explicitly kill daemons to let the test exit on Windows
$ killdaemons.py