##// 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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server.py
349 lines | 12.2 KiB | text/x-python | PythonLexer
# hgweb/server.py - The standalone hg web server.
#
# Copyright 21 May 2005 - (c) 2005 Jake Edge <jake@edge2.net>
# Copyright 2005-2007 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
import os, sys, errno, urllib, BaseHTTPServer, socket, SocketServer, traceback
from mercurial import util, error
from mercurial.hgweb import common
from mercurial.i18n import _
def _splitURI(uri):
"""Return path and query that has been split from uri
Just like CGI environment, the path is unquoted, the query is
not.
"""
if '?' in uri:
path, query = uri.split('?', 1)
else:
path, query = uri, ''
return urllib.unquote(path), query
class _error_logger(object):
def __init__(self, handler):
self.handler = handler
def flush(self):
pass
def write(self, str):
self.writelines(str.split('\n'))
def writelines(self, seq):
for msg in seq:
self.handler.log_error("HG error: %s", msg)
class _httprequesthandler(BaseHTTPServer.BaseHTTPRequestHandler):
url_scheme = 'http'
@staticmethod
def preparehttpserver(httpserver, ssl_cert):
"""Prepare .socket of new HTTPServer instance"""
pass
def __init__(self, *args, **kargs):
self.protocol_version = 'HTTP/1.1'
BaseHTTPServer.BaseHTTPRequestHandler.__init__(self, *args, **kargs)
def _log_any(self, fp, format, *args):
fp.write("%s - - [%s] %s\n" % (self.client_address[0],
self.log_date_time_string(),
format % args))
fp.flush()
def log_error(self, format, *args):
self._log_any(self.server.errorlog, format, *args)
def log_message(self, format, *args):
self._log_any(self.server.accesslog, format, *args)
def log_request(self, code='-', size='-'):
xheaders = []
if util.safehasattr(self, 'headers'):
xheaders = [h for h in self.headers.items()
if h[0].startswith('x-')]
self.log_message('"%s" %s %s%s',
self.requestline, str(code), str(size),
''.join([' %s:%s' % h for h in sorted(xheaders)]))
def do_write(self):
try:
self.do_hgweb()
except socket.error as inst:
if inst[0] != errno.EPIPE:
raise
def do_POST(self):
try:
self.do_write()
except Exception:
self._start_response("500 Internal Server Error", [])
self._write("Internal Server Error")
self._done()
tb = "".join(traceback.format_exception(*sys.exc_info()))
self.log_error("Exception happened during processing "
"request '%s':\n%s", self.path, tb)
def do_GET(self):
self.do_POST()
def do_hgweb(self):
path, query = _splitURI(self.path)
env = {}
env['GATEWAY_INTERFACE'] = 'CGI/1.1'
env['REQUEST_METHOD'] = self.command
env['SERVER_NAME'] = self.server.server_name
env['SERVER_PORT'] = str(self.server.server_port)
env['REQUEST_URI'] = self.path
env['SCRIPT_NAME'] = self.server.prefix
env['PATH_INFO'] = path[len(self.server.prefix):]
env['REMOTE_HOST'] = self.client_address[0]
env['REMOTE_ADDR'] = self.client_address[0]
if query:
env['QUERY_STRING'] = query
if self.headers.typeheader is None:
env['CONTENT_TYPE'] = self.headers.type
else:
env['CONTENT_TYPE'] = self.headers.typeheader
length = self.headers.getheader('content-length')
if length:
env['CONTENT_LENGTH'] = length
for header in [h for h in self.headers.keys()
if h not in ('content-type', 'content-length')]:
hkey = 'HTTP_' + header.replace('-', '_').upper()
hval = self.headers.getheader(header)
hval = hval.replace('\n', '').strip()
if hval:
env[hkey] = hval
env['SERVER_PROTOCOL'] = self.request_version
env['wsgi.version'] = (1, 0)
env['wsgi.url_scheme'] = self.url_scheme
if env.get('HTTP_EXPECT', '').lower() == '100-continue':
self.rfile = common.continuereader(self.rfile, self.wfile.write)
env['wsgi.input'] = self.rfile
env['wsgi.errors'] = _error_logger(self)
env['wsgi.multithread'] = isinstance(self.server,
SocketServer.ThreadingMixIn)
env['wsgi.multiprocess'] = isinstance(self.server,
SocketServer.ForkingMixIn)
env['wsgi.run_once'] = 0
self.saved_status = None
self.saved_headers = []
self.sent_headers = False
self.length = None
self._chunked = None
for chunk in self.server.application(env, self._start_response):
self._write(chunk)
if not self.sent_headers:
self.send_headers()
self._done()
def send_headers(self):
if not self.saved_status:
raise AssertionError("Sending headers before "
"start_response() called")
saved_status = self.saved_status.split(None, 1)
saved_status[0] = int(saved_status[0])
self.send_response(*saved_status)
self.length = None
self._chunked = False
for h in self.saved_headers:
self.send_header(*h)
if h[0].lower() == 'content-length':
self.length = int(h[1])
if (self.length is None and
saved_status[0] != common.HTTP_NOT_MODIFIED):
self._chunked = (not self.close_connection and
self.request_version == "HTTP/1.1")
if self._chunked:
self.send_header('Transfer-Encoding', 'chunked')
else:
self.send_header('Connection', 'close')
self.end_headers()
self.sent_headers = True
def _start_response(self, http_status, headers, exc_info=None):
code, msg = http_status.split(None, 1)
code = int(code)
self.saved_status = http_status
bad_headers = ('connection', 'transfer-encoding')
self.saved_headers = [h for h in headers
if h[0].lower() not in bad_headers]
return self._write
def _write(self, data):
if not self.saved_status:
raise AssertionError("data written before start_response() called")
elif not self.sent_headers:
self.send_headers()
if self.length is not None:
if len(data) > self.length:
raise AssertionError("Content-length header sent, but more "
"bytes than specified are being written.")
self.length = self.length - len(data)
elif self._chunked and data:
data = '%x\r\n%s\r\n' % (len(data), data)
self.wfile.write(data)
self.wfile.flush()
def _done(self):
if self._chunked:
self.wfile.write('0\r\n\r\n')
self.wfile.flush()
class _httprequesthandleropenssl(_httprequesthandler):
"""HTTPS handler based on pyOpenSSL"""
url_scheme = 'https'
@staticmethod
def preparehttpserver(httpserver, ssl_cert):
try:
import OpenSSL
OpenSSL.SSL.Context
except ImportError:
raise util.Abort(_("SSL support is unavailable"))
ctx = OpenSSL.SSL.Context(OpenSSL.SSL.TLSv1_METHOD)
ctx.use_privatekey_file(ssl_cert)
ctx.use_certificate_file(ssl_cert)
sock = socket.socket(httpserver.address_family, httpserver.socket_type)
httpserver.socket = OpenSSL.SSL.Connection(ctx, sock)
httpserver.server_bind()
httpserver.server_activate()
def setup(self):
self.connection = self.request
self.rfile = socket._fileobject(self.request, "rb", self.rbufsize)
self.wfile = socket._fileobject(self.request, "wb", self.wbufsize)
def do_write(self):
import OpenSSL
try:
_httprequesthandler.do_write(self)
except OpenSSL.SSL.SysCallError as inst:
if inst.args[0] != errno.EPIPE:
raise
def handle_one_request(self):
import OpenSSL
try:
_httprequesthandler.handle_one_request(self)
except (OpenSSL.SSL.SysCallError, OpenSSL.SSL.ZeroReturnError):
self.close_connection = True
pass
class _httprequesthandlerssl(_httprequesthandler):
"""HTTPS handler based on Pythons ssl module (introduced in 2.6)"""
url_scheme = 'https'
@staticmethod
def preparehttpserver(httpserver, ssl_cert):
try:
import ssl
ssl.wrap_socket
except ImportError:
raise util.Abort(_("SSL support is unavailable"))
httpserver.socket = ssl.wrap_socket(
httpserver.socket, server_side=True,
certfile=ssl_cert, ssl_version=ssl.PROTOCOL_TLSv1)
def setup(self):
self.connection = self.request
self.rfile = socket._fileobject(self.request, "rb", self.rbufsize)
self.wfile = socket._fileobject(self.request, "wb", self.wbufsize)
try:
from threading import activeCount
activeCount() # silence pyflakes
_mixin = SocketServer.ThreadingMixIn
except ImportError:
if util.safehasattr(os, "fork"):
_mixin = SocketServer.ForkingMixIn
else:
class _mixin(object):
pass
def openlog(opt, default):
if opt and opt != '-':
return open(opt, 'a')
return default
class MercurialHTTPServer(object, _mixin, BaseHTTPServer.HTTPServer):
# SO_REUSEADDR has broken semantics on windows
if os.name == 'nt':
allow_reuse_address = 0
def __init__(self, ui, app, addr, handler, **kwargs):
BaseHTTPServer.HTTPServer.__init__(self, addr, handler, **kwargs)
self.daemon_threads = True
self.application = app
handler.preparehttpserver(self, ui.config('web', 'certificate'))
prefix = ui.config('web', 'prefix', '')
if prefix:
prefix = '/' + prefix.strip('/')
self.prefix = prefix
alog = openlog(ui.config('web', 'accesslog', '-'), sys.stdout)
elog = openlog(ui.config('web', 'errorlog', '-'), sys.stderr)
self.accesslog = alog
self.errorlog = elog
self.addr, self.port = self.socket.getsockname()[0:2]
self.fqaddr = socket.getfqdn(addr[0])
class IPv6HTTPServer(MercurialHTTPServer):
address_family = getattr(socket, 'AF_INET6', None)
def __init__(self, *args, **kwargs):
if self.address_family is None:
raise error.RepoError(_('IPv6 is not available on this system'))
super(IPv6HTTPServer, self).__init__(*args, **kwargs)
def create_server(ui, app):
if ui.config('web', 'certificate'):
if sys.version_info >= (2, 6):
handler = _httprequesthandlerssl
else:
handler = _httprequesthandleropenssl
else:
handler = _httprequesthandler
if ui.configbool('web', 'ipv6'):
cls = IPv6HTTPServer
else:
cls = MercurialHTTPServer
# ugly hack due to python issue5853 (for threaded use)
try:
import mimetypes
mimetypes.init()
except UnicodeDecodeError:
# Python 2.x's mimetypes module attempts to decode strings
# from Windows' ANSI APIs as ascii (fail), then re-encode them
# as ascii (clown fail), because the default Python Unicode
# codec is hardcoded as ascii.
sys.argv # unwrap demand-loader so that reload() works
reload(sys) # resurrect sys.setdefaultencoding()
oldenc = sys.getdefaultencoding()
sys.setdefaultencoding("latin1") # or any full 8-bit encoding
mimetypes.init()
sys.setdefaultencoding(oldenc)
address = ui.config('web', 'address', '')
port = util.getport(ui.config('web', 'port', 8000))
try:
return cls(ui, app, (address, port), handler)
except socket.error as inst:
raise util.Abort(_("cannot start server at '%s:%d': %s")
% (address, port, inst.args[1]))