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 darcs

  $ echo "[extensions]" >> $HGRCPATH
  $ echo "convert=" >> $HGRCPATH
  $ DARCS_EMAIL='test@example.org'; export DARCS_EMAIL

initialize darcs repo

  $ mkdir darcs-repo
  $ cd darcs-repo
  $ darcs init -q
  $ echo a > a
  $ darcs record -a -l -m p0
  Finished recording patch 'p0'
  $ cd ..

branch and update

  $ darcs get -q darcs-repo darcs-clone >/dev/null
  $ cd darcs-clone
  $ echo c >> a
  $ echo c > c
  $ darcs record -a -l -m p1.1
  Finished recording patch 'p1.1'
  $ cd ..

skip if we can't import elementtree

  $ if hg convert darcs-repo darcs-dummy 2>&1 | grep ElementTree > /dev/null; then
  >     echo 'skipped: missing feature: elementtree module'
  >     exit 80
  > fi

update source

  $ cd darcs-repo
  $ echo b >> a
  $ echo b > b
  $ darcs record -a -l -m p1.2
  Finished recording patch 'p1.2'

  $ darcs pull -q -a --no-set-default ../darcs-clone
  Backing up ./a(*) (glob)
  We have conflicts in the following files:
  ./a
   (?)
  $ sleep 1
  $ echo e > a
  $ echo f > f
  $ mkdir dir
  $ echo d > dir/d
  $ echo d > dir/d2
  $ darcs record -a -l -m p2
  Finished recording patch 'p2'

test file and directory move

  $ darcs mv -q f ff

Test remove + move

  $ darcs remove -q dir/d2
  $ rm dir/d2
  $ darcs mv -q dir dir2
  $ darcs record -a -l -m p3
  Finished recording patch 'p3'

The converter does not currently handle patch conflicts very well.
When they occur, it reverts *all* changes and moves forward,
letting the conflict resolving patch fix collisions.
Unfortunately, non-conflicting changes, like the addition of the
"c" file in p1.1 patch are reverted too.
Just to say that manifest not listing "c" here is a bug.

  $ cd ..
  $ hg convert darcs-repo darcs-repo-hg
  initializing destination darcs-repo-hg repository
  scanning source...
  sorting...
  converting...
  4 p0
  3 p1.2
  2 p1.1
  1 p2
  0 p3
  $ hg log -R darcs-repo-hg -g --template '{rev} "{desc|firstline}" ({author}) files: {files}\n' "$@"
  4 "p3" (test@example.org) files: dir/d dir/d2 dir2/d f ff
  3 "p2" (test@example.org) files: a dir/d dir/d2 f
  2 "p1.1" (test@example.org) files: 
  1 "p1.2" (test@example.org) files: a b
  0 "p0" (test@example.org) files: a

  $ hg up -q -R darcs-repo-hg
  $ hg -R darcs-repo-hg manifest --debug
  7225b30cdf38257d5cc7780772c051b6f33e6d6b 644   a
  1e88685f5ddec574a34c70af492f95b6debc8741 644   b
  37406831adc447ec2385014019599dfec953c806 644   dir2/d
  b783a337463792a5c7d548ad85a7d3253c16ba8c 644   ff

#if no-outer-repo

try converting darcs1 repository

  $ hg clone -q "$TESTDIR/bundles/darcs1.hg" darcs
  $ hg convert -s darcs darcs/darcs1 2>&1 | grep darcs-1.0
  darcs-1.0 repository format is unsupported, please upgrade

#endif