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)
$ cat > makepatch.py <<EOF
> import sys
> f = open(sys.argv[2], 'wb')
> w = f.write
> w(b'test message\n')
> w(b'diff --git a/a b/a\n')
> w(b'--- a/a\n')
> w(b'+++ b/a\n')
> w(b'@@ -1,5 +1,5 @@\n')
> w(b' a\n')
> w(b'-bbb\r\n')
> w(b'+yyyy\r\n')
> w(b' cc\r\n')
> w({'empty:lf': b' \n',
> 'empty:crlf': b' \r\n',
> 'empty:stripped-lf': b'\n',
> 'empty:stripped-crlf': b'\r\n'}[sys.argv[1]])
> w(b' d\n')
> w(b'-e\n')
> w(b'\\\\ No newline at end of file\n')
> w(b'+z\r\n')
> w(b'\\\\ No newline at end of file\r\n')
> EOF
$ hg init repo
$ cd repo
$ echo '\.diff' > .hgignore
Test different --eol values
$ "$PYTHON" -c 'open("a", "wb").write(b"a\nbbb\ncc\n\nd\ne")'
$ hg ci -Am adda
adding .hgignore
adding a
$ "$PYTHON" ../makepatch.py empty:lf eol.diff
$ "$PYTHON" ../makepatch.py empty:crlf eol-empty-crlf.diff
$ "$PYTHON" ../makepatch.py empty:stripped-lf eol-empty-stripped-lf.diff
$ "$PYTHON" ../makepatch.py empty:stripped-crlf eol-empty-stripped-crlf.diff
invalid eol
$ hg --config patch.eol='LFCR' import eol.diff
applying eol.diff
abort: unsupported line endings type: LFCR
[255]
$ hg revert -a
force LF
$ hg --traceback --config patch.eol='LF' import eol.diff
applying eol.diff
$ hg id
9e4ef7b3d4af tip
$ cat a
a
yyyy
cc
d
e (no-eol)
$ hg st
(test empty-line variants: all of them should generate the same revision)
$ hg up -qC 0
$ hg --config patch.eol='LF' import eol-empty-crlf.diff
applying eol-empty-crlf.diff
$ hg id
9e4ef7b3d4af tip
$ hg up -qC 0
$ hg --config patch.eol='LF' import eol-empty-stripped-lf.diff
applying eol-empty-stripped-lf.diff
$ hg id
9e4ef7b3d4af tip
$ hg up -qC 0
$ hg --config patch.eol='LF' import eol-empty-stripped-crlf.diff
applying eol-empty-stripped-crlf.diff
$ hg id
9e4ef7b3d4af tip
force CRLF
$ hg up -C 0
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg --traceback --config patch.eol='CRLF' import eol.diff
applying eol.diff
$ cat a
a\r (esc)
yyyy\r (esc)
cc\r (esc)
\r (esc)
d\r (esc)
e (no-eol)
$ hg st
auto EOL on LF file
$ hg up -C 0
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg --traceback --config patch.eol='auto' import eol.diff
applying eol.diff
$ cat a
a
yyyy
cc
d
e (no-eol)
$ hg st
auto EOL on CRLF file
$ "$PYTHON" -c 'open("a", "wb").write(b"a\r\nbbb\r\ncc\r\n\r\nd\r\ne")'
$ hg commit -m 'switch EOLs in a'
$ hg --traceback --config patch.eol='auto' import eol.diff
applying eol.diff
$ cat a
a\r (esc)
yyyy\r (esc)
cc\r (esc)
\r (esc)
d\r (esc)
e (no-eol)
$ hg st
auto EOL on new file or source without any EOL
$ "$PYTHON" -c 'open("noeol", "wb").write(b"noeol")'
$ hg add noeol
$ hg commit -m 'add noeol'
$ "$PYTHON" -c 'open("noeol", "wb").write(b"noeol\r\nnoeol\n")'
$ "$PYTHON" -c 'open("neweol", "wb").write(b"neweol\nneweol\r\n")'
$ hg add neweol
$ hg diff --git > noeol.diff
$ hg revert --no-backup noeol neweol
$ rm neweol
$ hg --traceback --config patch.eol='auto' import -m noeol noeol.diff
applying noeol.diff
$ cat noeol
noeol\r (esc)
noeol
$ cat neweol
neweol
neweol\r (esc)
$ hg st
Test --eol and binary patches
$ "$PYTHON" -c 'open("b", "wb").write(b"a\x00\nb\r\nd")'
$ hg ci -Am addb
adding b
$ "$PYTHON" -c 'open("b", "wb").write(b"a\x00\nc\r\nd")'
$ hg diff --git > bin.diff
$ hg revert --no-backup b
binary patch with --eol
$ hg import --config patch.eol='CRLF' -m changeb bin.diff
applying bin.diff
$ cat b
a\x00 (esc)
c\r (esc)
d (no-eol)
$ hg st
$ cd ..