view contrib/hgweb.wsgi @ 40642:9c3c697267db

sparse-revlog: rework the way we enforce chunk size limit

We move from a O(N) algorithm to a O(log(N)) algorithm.

The previous algorithm was traversing the whole delta chain, looking for the
exact point where it became too big. This would result in most of the delta
chain to be traversed.

Instead, we now use a "binary" approach, slicing the chain in two until we
have a chunk of the appropriate size.

We still keep the previous algorithm for the snapshots part. There are few of
them and they are large bits of data distant from each other. So the previous
algorithm should work well in that case.

To take a practical example of restoring manifest revision '59547c40bc4c' for
a reference NetBeans repository (using sparse-revlog). The media time of the
step `slice-sparse-chain` of `perfrevlogrevision` improve from 1.109 ms to
0.660 ms.

# An example WSGI for use with mod_wsgi, edit as necessary
# See https://mercurial-scm.org/wiki/modwsgi for more information

# Path to repo or hgweb config to serve (see 'hg help hgweb')
config = "/path/to/repo/or/config"

# Uncomment and adjust if Mercurial is not installed system-wide
# (consult "installed modules" path from 'hg debuginstall'):
#import sys; sys.path.insert(0, "/path/to/python/lib")

# Uncomment to send python tracebacks to the browser if an error occurs:
#import cgitb; cgitb.enable()

# enable demandloading to reduce startup time
from mercurial import demandimport; demandimport.enable()

from mercurial.hgweb import hgweb
application = hgweb(config)