##// 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.

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httpconnection.py
284 lines | 10.6 KiB | text/x-python | PythonLexer
# httpconnection.py - urllib2 handler for new http support
#
# Copyright 2005, 2006, 2007, 2008 Matt Mackall <mpm@selenic.com>
# Copyright 2006, 2007 Alexis S. L. Carvalho <alexis@cecm.usp.br>
# Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.com>
# Copyright 2011 Google, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
import logging
import socket
import urllib
import urllib2
import os
from mercurial import httpclient
from mercurial import sslutil
from mercurial import util
from mercurial.i18n import _
# moved here from url.py to avoid a cycle
class httpsendfile(object):
"""This is a wrapper around the objects returned by python's "open".
Its purpose is to send file-like objects via HTTP.
It do however not define a __len__ attribute because the length
might be more than Py_ssize_t can handle.
"""
def __init__(self, ui, *args, **kwargs):
# We can't just "self._data = open(*args, **kwargs)" here because there
# is an "open" function defined in this module that shadows the global
# one
self.ui = ui
self._data = open(*args, **kwargs)
self.seek = self._data.seek
self.close = self._data.close
self.write = self._data.write
self.length = os.fstat(self._data.fileno()).st_size
self._pos = 0
self._total = self.length // 1024 * 2
def read(self, *args, **kwargs):
try:
ret = self._data.read(*args, **kwargs)
except EOFError:
self.ui.progress(_('sending'), None)
self._pos += len(ret)
# We pass double the max for total because we currently have
# to send the bundle twice in the case of a server that
# requires authentication. Since we can't know until we try
# once whether authentication will be required, just lie to
# the user and maybe the push succeeds suddenly at 50%.
self.ui.progress(_('sending'), self._pos // 1024,
unit=_('kb'), total=self._total)
return ret
# moved here from url.py to avoid a cycle
def readauthforuri(ui, uri, user):
# Read configuration
config = dict()
for key, val in ui.configitems('auth'):
if '.' not in key:
ui.warn(_("ignoring invalid [auth] key '%s'\n") % key)
continue
group, setting = key.rsplit('.', 1)
gdict = config.setdefault(group, dict())
if setting in ('username', 'cert', 'key'):
val = util.expandpath(val)
gdict[setting] = val
# Find the best match
scheme, hostpath = uri.split('://', 1)
bestuser = None
bestlen = 0
bestauth = None
for group, auth in config.iteritems():
if user and user != auth.get('username', user):
# If a username was set in the URI, the entry username
# must either match it or be unset
continue
prefix = auth.get('prefix')
if not prefix:
continue
p = prefix.split('://', 1)
if len(p) > 1:
schemes, prefix = [p[0]], p[1]
else:
schemes = (auth.get('schemes') or 'https').split()
if (prefix == '*' or hostpath.startswith(prefix)) and \
(len(prefix) > bestlen or (len(prefix) == bestlen and \
not bestuser and 'username' in auth)) \
and scheme in schemes:
bestlen = len(prefix)
bestauth = group, auth
bestuser = auth.get('username')
if user and not bestuser:
auth['username'] = user
return bestauth
# Mercurial (at least until we can remove the old codepath) requires
# that the http response object be sufficiently file-like, so we
# provide a close() method here.
class HTTPResponse(httpclient.HTTPResponse):
def close(self):
pass
class HTTPConnection(httpclient.HTTPConnection):
response_class = HTTPResponse
def request(self, method, uri, body=None, headers={}):
if isinstance(body, httpsendfile):
body.seek(0)
httpclient.HTTPConnection.request(self, method, uri, body=body,
headers=headers)
_configuredlogging = False
LOGFMT = '%(levelname)s:%(name)s:%(lineno)d:%(message)s'
# Subclass BOTH of these because otherwise urllib2 "helpfully"
# reinserts them since it notices we don't include any subclasses of
# them.
class http2handler(urllib2.HTTPHandler, urllib2.HTTPSHandler):
def __init__(self, ui, pwmgr):
global _configuredlogging
urllib2.AbstractHTTPHandler.__init__(self)
self.ui = ui
self.pwmgr = pwmgr
self._connections = {}
# developer config: ui.http2debuglevel
loglevel = ui.config('ui', 'http2debuglevel', default=None)
if loglevel and not _configuredlogging:
_configuredlogging = True
logger = logging.getLogger('mercurial.httpclient')
logger.setLevel(getattr(logging, loglevel.upper()))
handler = logging.StreamHandler()
handler.setFormatter(logging.Formatter(LOGFMT))
logger.addHandler(handler)
def close_all(self):
"""Close and remove all connection objects being kept for reuse."""
for openconns in self._connections.values():
for conn in openconns:
conn.close()
self._connections = {}
# shamelessly borrowed from urllib2.AbstractHTTPHandler
def do_open(self, http_class, req, use_ssl):
"""Return an addinfourl object for the request, using http_class.
http_class must implement the HTTPConnection API from httplib.
The addinfourl return value is a file-like object. It also
has methods and attributes including:
- info(): return a mimetools.Message object for the headers
- geturl(): return the original request URL
- code: HTTP status code
"""
# If using a proxy, the host returned by get_host() is
# actually the proxy. On Python 2.6.1, the real destination
# hostname is encoded in the URI in the urllib2 request
# object. On Python 2.6.5, it's stored in the _tunnel_host
# attribute which has no accessor.
tunhost = getattr(req, '_tunnel_host', None)
host = req.get_host()
if tunhost:
proxyhost = host
host = tunhost
elif req.has_proxy():
proxyhost = req.get_host()
host = req.get_selector().split('://', 1)[1].split('/', 1)[0]
else:
proxyhost = None
if proxyhost:
if ':' in proxyhost:
# Note: this means we'll explode if we try and use an
# IPv6 http proxy. This isn't a regression, so we
# won't worry about it for now.
proxyhost, proxyport = proxyhost.rsplit(':', 1)
else:
proxyport = 3128 # squid default
proxy = (proxyhost, proxyport)
else:
proxy = None
if not host:
raise urllib2.URLError('no host given')
connkey = use_ssl, host, proxy
allconns = self._connections.get(connkey, [])
conns = [c for c in allconns if not c.busy()]
if conns:
h = conns[0]
else:
if allconns:
self.ui.debug('all connections for %s busy, making a new '
'one\n' % host)
timeout = None
if req.timeout is not socket._GLOBAL_DEFAULT_TIMEOUT:
timeout = req.timeout
h = http_class(host, timeout=timeout, proxy_hostport=proxy)
self._connections.setdefault(connkey, []).append(h)
headers = dict(req.headers)
headers.update(req.unredirected_hdrs)
headers = dict(
(name.title(), val) for name, val in headers.items())
try:
path = req.get_selector()
if '://' in path:
path = path.split('://', 1)[1].split('/', 1)[1]
if path[0] != '/':
path = '/' + path
h.request(req.get_method(), path, req.data, headers)
r = h.getresponse()
except socket.error as err: # XXX what error?
raise urllib2.URLError(err)
# Pick apart the HTTPResponse object to get the addinfourl
# object initialized properly.
r.recv = r.read
resp = urllib.addinfourl(r, r.headers, req.get_full_url())
resp.code = r.status
resp.msg = r.reason
return resp
# httplib always uses the given host/port as the socket connect
# target, and then allows full URIs in the request path, which it
# then observes and treats as a signal to do proxying instead.
def http_open(self, req):
if req.get_full_url().startswith('https'):
return self.https_open(req)
def makehttpcon(*args, **kwargs):
k2 = dict(kwargs)
k2['use_ssl'] = False
return HTTPConnection(*args, **k2)
return self.do_open(makehttpcon, req, False)
def https_open(self, req):
# req.get_full_url() does not contain credentials and we may
# need them to match the certificates.
url = req.get_full_url()
user, password = self.pwmgr.find_stored_password(url)
res = readauthforuri(self.ui, url, user)
if res:
group, auth = res
self.auth = auth
self.ui.debug("using auth.%s.* for authentication\n" % group)
else:
self.auth = None
return self.do_open(self._makesslconnection, req, True)
def _makesslconnection(self, host, port=443, *args, **kwargs):
keyfile = None
certfile = None
if args: # key_file
keyfile = args.pop(0)
if args: # cert_file
certfile = args.pop(0)
# if the user has specified different key/cert files in
# hgrc, we prefer these
if self.auth and 'key' in self.auth and 'cert' in self.auth:
keyfile = self.auth['key']
certfile = self.auth['cert']
# let host port take precedence
if ':' in host and '[' not in host or ']:' in host:
host, port = host.rsplit(':', 1)
port = int(port)
if '[' in host:
host = host[1:-1]
kwargs['keyfile'] = keyfile
kwargs['certfile'] = certfile
kwargs.update(sslutil.sslkwargs(self.ui, host))
con = HTTPConnection(host, port, use_ssl=True,
ssl_wrap_socket=sslutil.wrapsocket,
ssl_validator=sslutil.validator(self.ui, host),
**kwargs)
return con