perf: clear vfs audit_cache before each run
When generating a stream clone, we spend a large amount of time auditing path.
Before this changes, the first run was warming the vfs cache for the other
runs, leading to a large runtime difference and a "faulty" reported timing for
the operation.
We now clear this important cache between run to get a more realistic timing.
Below are some example of median time change when clearing these cases. The
maximum time for a run did not changed significantly.
### data-env-vars.name = mozilla-central-2018-08-01-zstd-sparse-revlog
# benchmark.name = hg.perf.exchange.stream.generate
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
# benchmark.variants.version = latest
no-clearing: 17.289905
cache-clearing: 21.587965 (+24.86%, +4.30)
## data-env-vars.name = mozilla-central-2024-03-22-zstd-sparse-revlog
no-clearing: 32.670748
cache-clearing: 40.467095 (+23.86%, +7.80)
## data-env-vars.name = mozilla-try-2019-02-18-zstd-sparse-revlog
no-clearing: 37.838858
cache-clearing: 46.072749 (+21.76%, +8.23)
## data-env-vars.name = mozilla-unified-2024-03-22-zstd-sparse-revlog
no-clearing: 32.969395
cache-clearing: 39.646209 (+20.25%, +6.68)
In addition, this significantly reduce the timing difference between the
performance command, from the perf extensions and a `real `hg bundle` call
producing a stream bundle. Some significant differences remain especially on
the "mozilla-try" repositories, but they are now smaller.
Note that some of that difference will actually not be
attributable to the stream generation (like maybe phases or branch map
computation).
Below are some benchmarks done on a currently draft changeset fixing some
unrelated slowness in `hg bundle` (34a78972af409d1ff37c29e60f6ca811ad1a457d)
### data-env-vars.name = mozilla-central-2018-08-01-zstd-sparse-revlog
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
hg.perf.exchange.stream.generate: 21.587965
hg.command.bundle: 24.301799 (+12.57%, +2.71)
## data-env-vars.name = mozilla-central-2024-03-22-zstd-sparse-revlog
hg.perf.exchange.stream.generate: 40.467095
hg.command.bundle: 44.831317 (+10.78%, +4.36)
## data-env-vars.name = mozilla-unified-2024-03-22-zstd-sparse-revlog
hg.perf.exchange.stream.generate: 39.646209
hg.command.bundle: 45.395258 (+14.50%, +5.75)
## data-env-vars.name = mozilla-try-2019-02-18-zstd-sparse-revlog
hg.perf.exchange.stream.generate: 46.072749
hg.command.bundle: 55.882608 (+21.29%, +9.81)
## data-env-vars.name = mozilla-try-2023-03-22-zlib-general-delta
hg.perf.exchange.stream.generate: 334.716708
hg.command.bundle: 377.856767 (+12.89%, +43.14)
## data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
hg.perf.exchange.stream.generate: 302.972301
hg.command.bundle: 326.098755 (+7.63%, +23.13)
#require test-repo
$ . "$TESTDIR/helpers-testrepo.sh"
$ testrepohgenv
$ import_checker="$TESTDIR"/../contrib/import-checker.py
Run the doctests from the import checker, and make sure
it's working correctly.
$ TERM=dumb
$ export TERM
$ "$PYTHON" -m doctest $import_checker
Run additional tests for the import checker
$ mkdir testpackage
$ touch testpackage/__init__.py
$ cat > testpackage/multiple.py << EOF
> import os, sys
> EOF
$ cat > testpackage/unsorted.py << EOF
> import sys
> import os
> EOF
$ cat > testpackage/stdafterlocal.py << EOF
> from . import unsorted
> import os
> EOF
$ cat > testpackage/requirerelative.py << EOF
> import testpackage.unsorted
> EOF
$ cat > testpackage/importalias.py << EOF
> import ui
> EOF
$ cat > testpackage/relativestdlib.py << EOF
> from .. import os
> EOF
$ cat > testpackage/stdlibfrom.py << EOF
> from collections import abc
> EOF
$ cat > testpackage/symbolimport.py << EOF
> from .unsorted import foo
> EOF
$ cat > testpackage/latesymbolimport.py << EOF
> from . import unsorted
> from mercurial.node import hex
> EOF
$ cat > testpackage/multiplegroups.py << EOF
> from . import unsorted
> from . import more
> EOF
$ mkdir testpackage/subpackage
$ cat > testpackage/subpackage/levelpriority.py << EOF
> from . import foo
> from .. import parent
> EOF
$ touch testpackage/subpackage/foo.py
$ cat > testpackage/subpackage/__init__.py << EOF
> from . import levelpriority # should not cause cycle
> EOF
$ cat > testpackage/subpackage/localimport.py << EOF
> from . import foo
> def bar():
> # should not cause "higher-level import should come first"
> from .. import unsorted
> # but other errors should be detected
> from .. import more
> import testpackage.subpackage.levelpriority
> EOF
$ cat > testpackage/importmodulefromsub.py << EOF
> from .subpackage import foo # not a "direct symbol import"
> EOF
$ cat > testpackage/importsymbolfromsub.py << EOF
> from .subpackage import foo, nonmodule
> EOF
$ cat > testpackage/sortedentries.py << EOF
> from . import (
> foo,
> bar,
> )
> EOF
$ cat > testpackage/importfromalias.py << EOF
> from . import ui
> EOF
$ cat > testpackage/importfromrelative.py << EOF
> from testpackage.unsorted import foo
> EOF
$ mkdir testpackage2
$ touch testpackage2/__init__.py
$ cat > testpackage2/latesymbolimport.py << EOF
> from testpackage import unsorted
> from mercurial.node import hex
> EOF
# Shadowing a stdlib module to test "relative import of stdlib module" is
# allowed if the module is also being checked
$ mkdir email
$ touch email/__init__.py
$ touch email/errors.py
$ cat > email/utils.py << EOF
> from . import errors
> EOF
$ "$PYTHON" "$import_checker" testpackage*/*.py testpackage/subpackage/*.py \
> email/*.py
testpackage/importalias.py:1: ui module must be "as" aliased to uimod
testpackage/importfromalias.py:1: ui from testpackage must be "as" aliased to uimod
testpackage/importfromrelative.py:1: import should be relative: testpackage.unsorted
testpackage/importfromrelative.py:1: direct symbol import foo from testpackage.unsorted
testpackage/importsymbolfromsub.py:1: direct symbol import nonmodule from testpackage.subpackage
testpackage/latesymbolimport.py:2: symbol import follows non-symbol import: mercurial.node
testpackage/multiple.py:1: multiple imported names: os, sys
testpackage/multiplegroups.py:2: multiple "from . import" statements
testpackage/relativestdlib.py:1: relative import of stdlib module
testpackage/requirerelative.py:1: import should be relative: testpackage.unsorted
testpackage/sortedentries.py:1: imports from testpackage not lexically sorted: bar < foo
testpackage/stdafterlocal.py:2: stdlib import "os" follows local import: testpackage
testpackage/stdlibfrom.py:1: direct symbol import abc from collections
testpackage/subpackage/levelpriority.py:2: higher-level import should come first: testpackage
testpackage/subpackage/localimport.py:6: multiple "from .. import" statements
testpackage/subpackage/localimport.py:7: import should be relative: testpackage.subpackage.levelpriority
testpackage/symbolimport.py:1: direct symbol import foo from testpackage.unsorted
testpackage/unsorted.py:2: imports not lexically sorted: os < sys
testpackage2/latesymbolimport.py:2: symbol import follows non-symbol import: mercurial.node
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