delta: ignore base whose chains already don't match expectations
If we know the existing chain does not match our criteria, there is no point
to build a delta to append. This is especially useful when dealing with a full
text much smaller than its parent. In that case, the parent chain is probably
already too large.
example affected manifest write
before: 1.421005s
after: 0.815520s (-42%)
# 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)