view tests/test-propertycache.py @ 47120:7109a38830c9

dirstate-tree: Fold "tracked descendants" counter update in main walk

For the purpose of implementing `has_tracked_dir` (which means "has tracked
descendants) without an expensive sub-tree traversal, we maintaing a counter
of tracked descendants on each "directory" node of the tree-shaped dirstate.

Before this changeset, mutating or inserting a node at a given path would
involve:

* Walking the tree from root through ancestors to find the node or the spot
  where to insert it
* Looking at the previous node if any to decide what counter update is needed
* Performing any node mutation
* Walking the tree *again* to update counters in ancestor nodes

When profiling `hg status` on a large repo, this second walk takes times
while loading a the dirstate from disk.

It turns out we have enough information to decide before he first tree walk
what counter update is needed. This changeset merges the two walks, gaining
~10% of the total time for `hg update` (in the same hyperfine benchmark as
the previous changeset).

---

Profiling was done by compiling with this `.cargo/config`:

    [profile.release]
    debug = true

then running with:

    py-spy record -r 500 -n -o /tmp/hg.json --format speedscope -- \
    ./hg status -R $REPO --config experimental.dirstate-tree.in-memory=1

then visualizing the recorded JSON file in https://www.speedscope.app/

Differential Revision: https://phab.mercurial-scm.org/D10554

"""test behavior of propertycache and unfiltered propertycache

The repoview overlay is quite complex. We test the behavior of
property cache of both localrepo and repoview to prevent
regression."""

from __future__ import absolute_import, print_function
import os
import subprocess

from mercurial import (
    hg,
    localrepo,
    pycompat,
    ui as uimod,
    util,
)

from mercurial.utils import procutil

# create some special property cache that trace they call

calllog = []


@util.propertycache
def testcachedfoobar(repo):
    name = repo.filtername
    if name is None:
        name = ''
    val = len(name)
    calllog.append(val)
    return val


unficalllog = []


@localrepo.unfilteredpropertycache
def testcachedunfifoobar(repo):
    name = repo.filtername
    if name is None:
        name = ''
    val = 100 + len(name)
    unficalllog.append(val)
    return val


# plug them on repo
localrepo.localrepository.testcachedfoobar = testcachedfoobar
localrepo.localrepository.testcachedunfifoobar = testcachedunfifoobar


# Create an empty repo and instantiate it. It is important to run
# these tests on the real object to detect regression.
repopath = pycompat.fsencode(os.path.join(os.environ['TESTTMP'], 'repo'))
assert (
    subprocess.call(
        pycompat.rapply(procutil.tonativestr, [b'hg', b'init', repopath])
    )
    == 0
)

ui = uimod.ui.load()
repo = hg.repository(ui, path=repopath).unfiltered()


print('')
print('=== property cache ===')
print('')
print('calllog:', calllog)
print(
    'cached value (unfiltered):', vars(repo).get('testcachedfoobar', 'NOCACHE')
)

print('')
print('= first access on unfiltered, should do a call')
print('access:', repo.testcachedfoobar)
print('calllog:', calllog)
print(
    'cached value (unfiltered):', vars(repo).get('testcachedfoobar', 'NOCACHE')
)

print('')
print('= second access on unfiltered, should not do call')
print('access', repo.testcachedfoobar)
print('calllog:', calllog)
print(
    'cached value (unfiltered):', vars(repo).get('testcachedfoobar', 'NOCACHE')
)

print('')
print('= first access on "visible" view, should do a call')
visibleview = repo.filtered('visible')
print(
    'cached value ("visible" view):',
    vars(visibleview).get('testcachedfoobar', 'NOCACHE'),
)
print('access:', visibleview.testcachedfoobar)
print('calllog:', calllog)
print(
    'cached value (unfiltered):', vars(repo).get('testcachedfoobar', 'NOCACHE')
)
print(
    'cached value ("visible" view):',
    vars(visibleview).get('testcachedfoobar', 'NOCACHE'),
)

print('')
print('= second access on "visible view", should not do call')
print('access:', visibleview.testcachedfoobar)
print('calllog:', calllog)
print(
    'cached value (unfiltered):', vars(repo).get('testcachedfoobar', 'NOCACHE')
)
print(
    'cached value ("visible" view):',
    vars(visibleview).get('testcachedfoobar', 'NOCACHE'),
)

print('')
print('= no effect on other view')
immutableview = repo.filtered('immutable')
print(
    'cached value ("immutable" view):',
    vars(immutableview).get('testcachedfoobar', 'NOCACHE'),
)
print('access:', immutableview.testcachedfoobar)
print('calllog:', calllog)
print(
    'cached value (unfiltered):', vars(repo).get('testcachedfoobar', 'NOCACHE')
)
print(
    'cached value ("visible" view):',
    vars(visibleview).get('testcachedfoobar', 'NOCACHE'),
)
print(
    'cached value ("immutable" view):',
    vars(immutableview).get('testcachedfoobar', 'NOCACHE'),
)

# unfiltered property cache test
print('')
print('')
print('=== unfiltered property cache ===')
print('')
print('unficalllog:', unficalllog)
print(
    'cached value (unfiltered):      ',
    vars(repo).get('testcachedunfifoobar', 'NOCACHE'),
)
print(
    'cached value ("visible" view):  ',
    vars(visibleview).get('testcachedunfifoobar', 'NOCACHE'),
)
print(
    'cached value ("immutable" view):',
    vars(immutableview).get('testcachedunfifoobar', 'NOCACHE'),
)

print('')
print('= first access on unfiltered, should do a call')
print('access (unfiltered):', repo.testcachedunfifoobar)
print('unficalllog:', unficalllog)
print(
    'cached value (unfiltered):      ',
    vars(repo).get('testcachedunfifoobar', 'NOCACHE'),
)

print('')
print('= second access on unfiltered, should not do call')
print('access (unfiltered):', repo.testcachedunfifoobar)
print('unficalllog:', unficalllog)
print(
    'cached value (unfiltered):      ',
    vars(repo).get('testcachedunfifoobar', 'NOCACHE'),
)

print('')
print('= access on view should use the unfiltered cache')
print('access (unfiltered):      ', repo.testcachedunfifoobar)
print('access ("visible" view):  ', visibleview.testcachedunfifoobar)
print('access ("immutable" view):', immutableview.testcachedunfifoobar)
print('unficalllog:', unficalllog)
print(
    'cached value (unfiltered):      ',
    vars(repo).get('testcachedunfifoobar', 'NOCACHE'),
)
print(
    'cached value ("visible" view):  ',
    vars(visibleview).get('testcachedunfifoobar', 'NOCACHE'),
)
print(
    'cached value ("immutable" view):',
    vars(immutableview).get('testcachedunfifoobar', 'NOCACHE'),
)

print('')
print('= even if we clear the unfiltered cache')
del repo.__dict__['testcachedunfifoobar']
print(
    'cached value (unfiltered):      ',
    vars(repo).get('testcachedunfifoobar', 'NOCACHE'),
)
print(
    'cached value ("visible" view):  ',
    vars(visibleview).get('testcachedunfifoobar', 'NOCACHE'),
)
print(
    'cached value ("immutable" view):',
    vars(immutableview).get('testcachedunfifoobar', 'NOCACHE'),
)
print('unficalllog:', unficalllog)
print('access ("visible" view):  ', visibleview.testcachedunfifoobar)
print('unficalllog:', unficalllog)
print(
    'cached value (unfiltered):      ',
    vars(repo).get('testcachedunfifoobar', 'NOCACHE'),
)
print(
    'cached value ("visible" view):  ',
    vars(visibleview).get('testcachedunfifoobar', 'NOCACHE'),
)
print(
    'cached value ("immutable" view):',
    vars(immutableview).get('testcachedunfifoobar', 'NOCACHE'),
)
print('access ("immutable" view):', immutableview.testcachedunfifoobar)
print('unficalllog:', unficalllog)
print(
    'cached value (unfiltered):      ',
    vars(repo).get('testcachedunfifoobar', 'NOCACHE'),
)
print(
    'cached value ("visible" view):  ',
    vars(visibleview).get('testcachedunfifoobar', 'NOCACHE'),
)
print(
    'cached value ("immutable" view):',
    vars(immutableview).get('testcachedunfifoobar', 'NOCACHE'),
)
print('access (unfiltered):      ', repo.testcachedunfifoobar)
print('unficalllog:', unficalllog)
print(
    'cached value (unfiltered):      ',
    vars(repo).get('testcachedunfifoobar', 'NOCACHE'),
)
print(
    'cached value ("visible" view):  ',
    vars(visibleview).get('testcachedunfifoobar', 'NOCACHE'),
)
print(
    'cached value ("immutable" view):',
    vars(immutableview).get('testcachedunfifoobar', 'NOCACHE'),
)