##// END OF EJS Templates
revlog: change generaldelta delta parent heuristic...
revlog: change generaldelta delta parent heuristic The old generaldelta heuristic was "if p1 (or p2) was closer than the last full text, use it, otherwise use prev". This was problematic when a repo contained multiple branches that were very different. If commits to branch A were pushed, and the last full text was branch B, it would generate a fulltext. Then if branch B was pushed, it would generate another fulltext. The problem is that the last fulltext (and delta'ing against `prev` in general) has no correlation with the contents of the incoming revision, and therefore will always have degenerate cases. According to the blame, that algorithm was chosen to minimize the chain length. Since there is already code that protects against that (the delta-vs-fulltext code), and since it has been improved since the original generaldelta algorithm went in (2011), I believe the chain length criteria will still be preserved. The new algorithm always diffs against p1 (or p2 if it's closer), unless the resulting delta will fail the delta-vs-fulltext check, in which case we delta against prev. Some before and after stats on manifest.d size. internal large repo old heuristic - 2.0 GB new heuristic - 1.2 GB mozilla-central old heuristic - 242 MB new heuristic - 261 MB The regression in mozilla central is due to the new heuristic choosing p2r as the delta when it's closer to the tip. Switching the algorithm to always prefer p1r brings the size back down (242 MB). This is result of the way in which mozilla does merges and pushes, and the result could easily swing the other direction in other repos (depending on if they merge X into Y or Y into X), but will never be as degenerate as before. I future patch will address the regression by introducing an optional, even more aggressive delta heuristic which will knock the mozilla manifest size down dramatically.

File last commit:

r22198:77142de4 default
r26117:4dc5b51f default
Show More
hgwebdir_wsgi.py
96 lines | 3.3 KiB | text/x-python | PythonLexer
# An example WSGI script for IIS/isapi-wsgi to export multiple hgweb repos
# Copyright 2010 Sune Foldager <cryo@cyanite.org>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
#
# Requirements:
# - Python 2.6
# - PyWin32 build 214 or newer
# - Mercurial installed from source (python setup.py install)
# - IIS 7
#
# Earlier versions will in general work as well, but the PyWin32 version is
# necessary for win32traceutil to work correctly.
#
#
# Installation and use:
#
# - Download the isapi-wsgi source and run python setup.py install:
# http://code.google.com/p/isapi-wsgi/
#
# - Run this script (i.e. python hgwebdir_wsgi.py) to get a shim dll. The
# shim is identical for all scripts, so you can just copy and rename one
# from an earlier run, if you wish.
#
# - Setup an IIS application where your hgwebdir is to be served from.
# On 64-bit systems, make sure it's assigned a 32-bit app pool.
#
# - In the application, setup a wildcard script handler mapping of type
# IsapiModule with the shim dll as its executable. This file MUST reside
# in the same directory as the shim. Remove all other handlers, if you wish.
#
# - Make sure the ISAPI and CGI restrictions (configured globally on the
# web server) includes the shim dll, to allow it to run.
#
# - Adjust the configuration variables below to match your needs.
#
# Configuration file location
hgweb_config = r'c:\src\iis\hg\hgweb.config'
# Global settings for IIS path translation
path_strip = 0 # Strip this many path elements off (when using url rewrite)
path_prefix = 1 # This many path elements are prefixes (depends on the
# virtual path of the IIS application).
import sys
# Adjust python path if this is not a system-wide install
#sys.path.insert(0, r'c:\path\to\python\lib')
# Enable tracing. Run 'python -m win32traceutil' to debug
if getattr(sys, 'isapidllhandle', None) is not None:
import win32traceutil
win32traceutil.SetupForPrint # silence unused import warning
# To serve pages in local charset instead of UTF-8, remove the two lines below
import os
os.environ['HGENCODING'] = 'UTF-8'
import isapi_wsgi
from mercurial import demandimport; demandimport.enable()
from mercurial.hgweb.hgwebdir_mod import hgwebdir
# Example tweak: Replace isapi_wsgi's handler to provide better error message
# Other stuff could also be done here, like logging errors etc.
class WsgiHandler(isapi_wsgi.IsapiWsgiHandler):
error_status = '500 Internal Server Error' # less silly error message
isapi_wsgi.IsapiWsgiHandler = WsgiHandler
# Only create the hgwebdir instance once
application = hgwebdir(hgweb_config)
def handler(environ, start_response):
# Translate IIS's weird URLs
url = environ['SCRIPT_NAME'] + environ['PATH_INFO']
paths = url[1:].split('/')[path_strip:]
script_name = '/' + '/'.join(paths[:path_prefix])
path_info = '/'.join(paths[path_prefix:])
if path_info:
path_info = '/' + path_info
environ['SCRIPT_NAME'] = script_name
environ['PATH_INFO'] = path_info
return application(environ, start_response)
def __ExtensionFactory__():
return isapi_wsgi.ISAPISimpleHandler(handler)
if __name__=='__main__':
from isapi.install import ISAPIParameters, HandleCommandLine
params = ISAPIParameters()
HandleCommandLine(params)