Mercurial > hg
view tests/test-journal.t @ 47802:de2e04fe4897
hgwebdir: avoid systematic full garbage collection
Forcing a systematic full garbage collection upon each request
can serioulsy harm performance. This is reported as
https://bz.mercurial-scm.org/show_bug.cgi?id=6075
With this change we're performing the full collection according
to a new setting, `experimental.web.full-garbage-collection-rate`.
The default value is 1, which doesn't change the behavior and will
allow us to test on real use cases. If the value is 0, no full garbage
collection occurs.
Regardless of the value of the setting, a partial garbage collection
still occurs upon each request (not attempting to collect objects from
the oldest generation). This should be enough to take care of
reference cycles that have been created by the last request
(assessment of this requires changing the setting, not to be 1).
In my experience chasing memory leaks in Mercurial servers,
the full collection never reclaimed any memory, but this is with
Python 3 and biased towards small repositories.
On the other hand, as explained in the Python developer docs [1],
frequent full collections are very harmful in terms of performance if
lots of objects survive the collection, and hence stay in the
oldest generation. Note that `gc.collect()` is indeed trying to
collect the oldest generation [2]. This happens usually in two cases:
- unwanted lingering objects (i.e., an actual memory leak that
the GC cannot do anything about). Sadly, we have lots of those
these days.
- desireable long-term objects, typically in caches (not inner caches
carried by repositories, which should be collected with them). This
is a subject of interest for the Heptapod project.
In short, the flat rate that this change still permits is
probably a bad idea in most cases, and the default value can
be tweaked later on (or even be set to 0) according to experiments
in the wild.
The test is inspired from test-hgwebdir-paths.py
[1] https://devguide.python.org/garbage_collector/#collecting-the-oldest-generation
[2] https://docs.python.org/3/library/gc.html#gc.collect
Differential Revision: https://phab.mercurial-scm.org/D11204
author | Georges Racinet <georges.racinet@octobus.net> |
---|---|
date | Tue, 20 Jul 2021 17:20:19 +0200 |
parents | ef6cab7930b3 |
children | 8ef9cdffad6a |
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Tests for the journal extension; records bookmark locations. $ cat >> testmocks.py << EOF > # mock out procutil.getuser() and util.makedate() to supply testable values > import os > from mercurial import pycompat, util > from mercurial.utils import dateutil, procutil > def mockgetuser(): > return b'foobar' > > def mockmakedate(): > filename = os.path.join(os.environ['TESTTMP'], 'testtime') > try: > with open(filename, 'rb') as timef: > time = float(timef.read()) + 1 > except IOError: > time = 0.0 > with open(filename, 'wb') as timef: > timef.write(pycompat.bytestr(time)) > return (time, 0) > > procutil.getuser = mockgetuser > dateutil.makedate = mockmakedate > EOF $ cat >> $HGRCPATH << EOF > [extensions] > journal= > testmocks=`pwd`/testmocks.py > EOF Setup repo $ hg init repo $ cd repo Test empty journal $ hg journal previous locations of '.': no recorded locations $ hg journal foo previous locations of 'foo': no recorded locations Test that working copy changes are tracked $ echo a > a $ hg commit -Aqm a $ hg journal previous locations of '.': cb9a9f314b8b commit -Aqm a $ echo b > a $ hg commit -Aqm b $ hg journal previous locations of '.': 1e6c11564562 commit -Aqm b cb9a9f314b8b commit -Aqm a $ hg up 0 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ hg journal previous locations of '.': cb9a9f314b8b up 0 1e6c11564562 commit -Aqm b cb9a9f314b8b commit -Aqm a Test that bookmarks are tracked $ hg book -r tip bar $ hg journal bar previous locations of 'bar': 1e6c11564562 book -r tip bar $ hg book -f bar $ hg journal bar previous locations of 'bar': cb9a9f314b8b book -f bar 1e6c11564562 book -r tip bar $ hg up 1 files updated, 0 files merged, 0 files removed, 0 files unresolved updating bookmark bar $ hg journal bar previous locations of 'bar': 1e6c11564562 up cb9a9f314b8b book -f bar 1e6c11564562 book -r tip bar Test that bookmarks and working copy tracking is not mixed $ hg journal previous locations of '.': 1e6c11564562 up cb9a9f314b8b up 0 1e6c11564562 commit -Aqm b cb9a9f314b8b commit -Aqm a Test that you can list all entries as well as limit the list or filter on them $ hg book -r tip baz $ hg journal --all previous locations of the working copy and bookmarks: 1e6c11564562 baz book -r tip baz 1e6c11564562 bar up 1e6c11564562 . up cb9a9f314b8b bar book -f bar 1e6c11564562 bar book -r tip bar cb9a9f314b8b . up 0 1e6c11564562 . commit -Aqm b cb9a9f314b8b . commit -Aqm a $ hg journal --limit 2 previous locations of '.': 1e6c11564562 up cb9a9f314b8b up 0 $ hg journal bar previous locations of 'bar': 1e6c11564562 up cb9a9f314b8b book -f bar 1e6c11564562 book -r tip bar $ hg journal foo previous locations of 'foo': no recorded locations $ hg journal . previous locations of '.': 1e6c11564562 up cb9a9f314b8b up 0 1e6c11564562 commit -Aqm b cb9a9f314b8b commit -Aqm a $ hg journal "re:ba." previous locations of 're:ba.': 1e6c11564562 baz book -r tip baz 1e6c11564562 bar up cb9a9f314b8b bar book -f bar 1e6c11564562 bar book -r tip bar Test that verbose, JSON, template and commit output work $ hg journal --verbose --all previous locations of the working copy and bookmarks: 000000000000 -> 1e6c11564562 foobar baz 1970-01-01 00:00 +0000 book -r tip baz cb9a9f314b8b -> 1e6c11564562 foobar bar 1970-01-01 00:00 +0000 up cb9a9f314b8b -> 1e6c11564562 foobar . 1970-01-01 00:00 +0000 up 1e6c11564562 -> cb9a9f314b8b foobar bar 1970-01-01 00:00 +0000 book -f bar 000000000000 -> 1e6c11564562 foobar bar 1970-01-01 00:00 +0000 book -r tip bar 1e6c11564562 -> cb9a9f314b8b foobar . 1970-01-01 00:00 +0000 up 0 cb9a9f314b8b -> 1e6c11564562 foobar . 1970-01-01 00:00 +0000 commit -Aqm b 000000000000 -> cb9a9f314b8b foobar . 1970-01-01 00:00 +0000 commit -Aqm a $ hg journal --verbose -Tjson [ { "command": "up", "date": [5, 0], "name": ".", "newnodes": ["1e6c11564562b4ed919baca798bc4338bd299d6a"], "oldnodes": ["cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b"], "user": "foobar" }, { "command": "up 0", "date": [2, 0], "name": ".", "newnodes": ["cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b"], "oldnodes": ["1e6c11564562b4ed919baca798bc4338bd299d6a"], "user": "foobar" }, { "command": "commit -Aqm b", "date": [1, 0], "name": ".", "newnodes": ["1e6c11564562b4ed919baca798bc4338bd299d6a"], "oldnodes": ["cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b"], "user": "foobar" }, { "command": "commit -Aqm a", "date": [0, 0], "name": ".", "newnodes": ["cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b"], "oldnodes": ["0000000000000000000000000000000000000000"], "user": "foobar" } ] $ cat <<EOF >> $HGRCPATH > [templates] > j = "{oldnodes % '{node|upper}'} -> {newnodes % '{node|upper}'} > - user: {user} > - command: {command} > - date: {date|rfc3339date} > - newnodes: {newnodes} > - oldnodes: {oldnodes} > " > EOF $ hg journal -Tj -l1 previous locations of '.': CB9A9F314B8B07BA71012FCDBC544B5A4D82FF5B -> 1E6C11564562B4ED919BACA798BC4338BD299D6A - user: foobar - command: up - date: 1970-01-01T00:00:05+00:00 - newnodes: 1e6c11564562b4ed919baca798bc4338bd299d6a - oldnodes: cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b $ hg journal --commit previous locations of '.': 1e6c11564562 up changeset: 1:1e6c11564562 bookmark: bar bookmark: baz tag: tip user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: b cb9a9f314b8b up 0 changeset: 0:cb9a9f314b8b user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: a 1e6c11564562 commit -Aqm b changeset: 1:1e6c11564562 bookmark: bar bookmark: baz tag: tip user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: b cb9a9f314b8b commit -Aqm a changeset: 0:cb9a9f314b8b user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: a $ hg journal --commit -Tjson [ { "changesets": [{"bookmarks": ["bar", "baz"], "branch": "default", "date": [0, 0], "desc": "b", "node": "1e6c11564562b4ed919baca798bc4338bd299d6a", "parents": ["cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b"], "phase": "draft", "rev": 1, "tags": ["tip"], "user": "test"}], "command": "up", "date": [5, 0], "name": ".", "newnodes": ["1e6c11564562b4ed919baca798bc4338bd299d6a"], "oldnodes": ["cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b"], "user": "foobar" }, { "changesets": [{"bookmarks": [], "branch": "default", "date": [0, 0], "desc": "a", "node": "cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b", "parents": ["0000000000000000000000000000000000000000"], "phase": "draft", "rev": 0, "tags": [], "user": "test"}], "command": "up 0", "date": [2, 0], "name": ".", "newnodes": ["cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b"], "oldnodes": ["1e6c11564562b4ed919baca798bc4338bd299d6a"], "user": "foobar" }, { "changesets": [{"bookmarks": ["bar", "baz"], "branch": "default", "date": [0, 0], "desc": "b", "node": "1e6c11564562b4ed919baca798bc4338bd299d6a", "parents": ["cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b"], "phase": "draft", "rev": 1, "tags": ["tip"], "user": "test"}], "command": "commit -Aqm b", "date": [1, 0], "name": ".", "newnodes": ["1e6c11564562b4ed919baca798bc4338bd299d6a"], "oldnodes": ["cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b"], "user": "foobar" }, { "changesets": [{"bookmarks": [], "branch": "default", "date": [0, 0], "desc": "a", "node": "cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b", "parents": ["0000000000000000000000000000000000000000"], "phase": "draft", "rev": 0, "tags": [], "user": "test"}], "command": "commit -Aqm a", "date": [0, 0], "name": ".", "newnodes": ["cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b"], "oldnodes": ["0000000000000000000000000000000000000000"], "user": "foobar" } ] $ hg journal --commit \ > -T'command: {command}\n{changesets % " rev: {rev}\n children: {children}\n"}' previous locations of '.': command: up rev: 1 children: command: up 0 rev: 0 children: 1:1e6c11564562 command: commit -Aqm b rev: 1 children: command: commit -Aqm a rev: 0 children: 1:1e6c11564562 Test for behaviour on unexpected storage version information $ printf '42\0' > .hg/namejournal $ hg journal previous locations of '.': abort: unknown journal file version '42' [255] $ hg book -r tip doomed unsupported journal file version '42'