New submission from Kristján Valur Jónsson <[EMAIL PROTECTED]>: There are two performance problems in xmlrpclib.py: POST requests use two send() calls, one to send the headers and one to send the data. This can invoke the Nagle/Delayed ACK performance problem. On many socket implementations (including some windows platforms) it can introduce delays of up to 200ms when talking over the wire (as opposed to localhost) The second is the use of no buffering when reading the xmlrpc response. It is done using the readline() call on a file-like object constructed from the socket. When no buffering is in effect, this causes a separate recv() call for each character.
This patch fixes these issues separately: 1) We provide a new getheaderdata() function in httplib which just returns the data for the headers instead of sending it. This can be used instead of endheaders() if the intention is to subsequently send more data. xmlrpclib then uses this method of framing its POST messages. 2) We provide the named artgument bufsize=0 to the HTTPResponse class in httplib, and also so on for the HTTPConnection.getresponse() and HTTP.getreply(). xmlrpclib then passes bufsize=-1 to HTTP.getreply() to get default buffering for the response fileobject. This patch focuses on fixing the problems with xmlrpclib. but issue 1) above also has a number of other manifestations in the lib, there are other places where we can use getheaderdata() and send() instead of endheaders() to avoid possible Nagle/Ack problems, e.g. in urllib.py, distutils.py and loggin/handlers.py ---------- components: Extension Modules files: xmlrpc.patch keywords: easy, patch, patch messages: 75962 nosy: krisvale severity: normal status: open title: Fix performance issues in xmlrpclib type: performance versions: Python 2.7 Added file: http://bugs.python.org/file12030/xmlrpc.patch _______________________________________ Python tracker <[EMAIL PROTECTED]> <http://bugs.python.org/issue4336> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
