[server] Make connection pooler configurable and set better default values
Drop the configuration connections-pool-size and add new configurations options:
* connections-pool-min-size. Set to 0 by default so we open connections only
when needed. This avoid opening min-size*processes connections at startup,
which is, it think, a good default.
* connections-pool-max-size. Set to 0 (unlimited) by default, so we move the
bottleneck to postgresql.
* connections-idle-timeout. Set to 10 minutes. I don't have arguments about
this except that this is the default in pgbouncer.
# copyright 2003-2011 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
#
# This file is part of CubicWeb.
#
# CubicWeb is free software: you can redistribute it and/or modify it under the
# terms of the GNU Lesser General Public License as published by the Free
# Software Foundation, either version 2.1 of the License, or (at your option)
# any later version.
#
# CubicWeb is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
# details.
#
# You should have received a copy of the GNU Lesser General Public License along
# with CubicWeb. If not, see <http://www.gnu.org/licenses/>.
"""This package contains all WSGI specific code for cubicweb
NOTE: this package borrows a lot of code to Django
(http://www.djangoproject.com) and to the wsgiref module
of the python2.5's stdlib.
WSGI corresponding PEP: http://www.python.org/dev/peps/pep-0333/
"""
from email import message, message_from_string
from http.cookies import SimpleCookie
from pprint import pformat as _pformat
def pformat(obj):
"""pretty prints `obj` if possible"""
try:
return _pformat(obj)
except Exception:
return u'<could not parse>'
def normalize_header(header):
"""returns a normalized header name
>>> normalize_header('User_Agent')
'User-agent'
"""
return header.replace('_', '-').capitalize()
def safe_copyfileobj(fsrc, fdst, length=16*1024, size=0):
"""
THIS COMES FROM DJANGO
A version of shutil.copyfileobj that will not read more than 'size' bytes.
This makes it safe from clients sending more than CONTENT_LENGTH bytes of
data in the body.
"""
if not size:
return
while size > 0:
buf = fsrc.read(min(length, size))
if not buf:
break
fdst.write(buf)
size -= len(buf)