tests/test-serve.t

obsolete: order of magnitude speedup in _computebumpedset

Reminder: a changeset is said "bumped" if it tries to obsolete a immutable
          changeset.


The previous algorithm for computing bumped changeset was:

    1) Get all public changesets
    2) Find all they successors
    3) Search for stuff that are eligible for being "bumped"
       (mutable and non obsolete)

The entry size of this algorithm is `O(len(public))` which is mostly the same as
`O(len(repo))`. Even this this approach mean fewer obsolescence marker are
traveled, this is not very scalable.

The new algorithm is:

    1) For each potential bumped changesets (non obsolete mutable)
    2) iterate over precursors
    3) if a precursors is public. changeset is bumped

We travel more obsolescence marker, but the entry size is much smaller since
the amount of potential bumped should remains mostly stable with time `O(1)`.

On some confidential gigantic repo this move bumped computation from 15.19s to
0.46s (×33 speedup…). On "smaller" repo (mercurial, cubicweb's review) no
significant gain were seen. The additional traversal of obsolescence marker is
probably probably counter balance the advantage of it.

Other optimisation could be done in the future (eg: sharing precursors cache
for divergence detection)

  $ "$TESTDIR/hghave" serve || exit 80

  $ hgserve()
  > {
  >    hg serve -a localhost -d --pid-file=hg.pid -E errors.log -v $@ \
  >        | sed -e "s/:$HGPORT1\\([^0-9]\\)/:HGPORT1\1/g" \
  >              -e "s/:$HGPORT2\\([^0-9]\\)/:HGPORT2\1/g" \
  >              -e 's/http:\/\/[^/]*\//http:\/\/localhost\//'
  >    cat hg.pid >> "$DAEMON_PIDS"
  >    echo % errors
  >    cat errors.log
  >    "$TESTDIR/killdaemons.py" hg.pid
  > }

  $ hg init test
  $ cd test
  $ echo '[web]' > .hg/hgrc
  $ echo 'accesslog = access.log' >> .hg/hgrc
  $ echo "port = $HGPORT1" >> .hg/hgrc

Without -v

  $ hg serve -a localhost -p $HGPORT -d --pid-file=hg.pid -E errors.log
  $ cat hg.pid >> "$DAEMON_PIDS"
  $ if [ -f access.log ]; then
  >     echo 'access log created - .hg/hgrc respected'
  > fi
  access log created - .hg/hgrc respected

errors

  $ cat errors.log

With -v

  $ hgserve
  listening at http://localhost/ (bound to 127.0.0.1:HGPORT1)
  % errors

With -v and -p HGPORT2

  $ hgserve -p "$HGPORT2"
  listening at http://localhost/ (bound to 127.0.0.1:HGPORT2)
  % errors

With -v and -p daytime (should fail because low port)

#if no-root
  $ KILLQUIETLY=Y
  $ hgserve -p daytime
  abort: cannot start server at 'localhost:13': Permission denied
  abort: child process failed to start
  % errors
  $ KILLQUIETLY=N
#endif

With --prefix foo

  $ hgserve --prefix foo
  listening at http://localhost/foo/ (bound to 127.0.0.1:HGPORT1)
  % errors

With --prefix /foo

  $ hgserve --prefix /foo
  listening at http://localhost/foo/ (bound to 127.0.0.1:HGPORT1)
  % errors

With --prefix foo/

  $ hgserve --prefix foo/
  listening at http://localhost/foo/ (bound to 127.0.0.1:HGPORT1)
  % errors

With --prefix /foo/

  $ hgserve --prefix /foo/
  listening at http://localhost/foo/ (bound to 127.0.0.1:HGPORT1)
  % errors

  $ cd ..