view hgweb.cgi @ 23226:5dcaed20b27c stable

changegroup: sparsely populate fnodes

Previously, fnodes had a key and empty dict value for every element in
changedfiles. This is somewhat wasteful. Empty dicts in CPython consume
a lot more memory than you would expect - 280 bytes.

On mozilla-central, which has ~190,000 files/fnodes keys, the previous
loop populating fnodes allocated 91,924 KB of memory, most of that for
the empty dicts.

With this patch in place, our peak RSS during mozilla-central clone
drops:

before:  364,356 KB
after:   326,008 KB
delta:   -38,348 KB

When combined with the previous patch, total peak RSS decrease is now
190,116 KB.

#!/usr/bin/env python
#
# An example hgweb CGI script, edit as necessary
# See also http://mercurial.selenic.com/wiki/PublishingRepositories

# 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()

from mercurial import demandimport; demandimport.enable()
from mercurial.hgweb import hgweb, wsgicgi
application = hgweb(config)
wsgicgi.launch(application)