view tests/test-bad-pull.t @ 51108:0250e45040f1

revlog: add a small cache of unfiltered chunk

This can provides a massive boost to the reading of multiple revision and the
computation of a valid delta chain.

This greatly help operation like `hg log --patch`, delta computation (helping
pull/unbundle), linkrev adjustment (helping copy tracing).

A first round of benchmark for `hg log --patch --limit 1000` shows improvement
in the 10-20% range on "small" repository like pypy or mercurial and large
improvements (about 33%) for more complex ones like netbeans and mozilla's.

These speeds up are consistent with the improvement to `hg pull` (from a server
sending poor deltas) I saw benchmarking this last year. Further benchmark will
be run during the freeze.

I added some configuration in the experimental space to be able to further test
the effect of various tuning for now. This feature should fit well in the
"usage/resource profile" configuration that we should land next cycle.

When it does not provides a benefit the overhead of the cache seem to be around
2%, a small price for the big improvement. In addition I believe we could shave
most of this overhead with a more efficent lru implementation.

#require serve

  $ hg clone http://localhost:$HGPORT/ copy
  abort: * (glob)
  [100]

  $ test -d copy
  [1]

  $ "$PYTHON" "$TESTDIR/dumbhttp.py" -p $HGPORT --pid dumb.pid
  $ cat dumb.pid >> $DAEMON_PIDS
  $ hg clone http://localhost:$HGPORT/foo copy2
  abort: HTTP Error 404: * (glob)
  [100]
  $ killdaemons.py