[mod_python] scalability question?

What Apache MPM is each server compiled with, prefork or worker MPM?

Graham

On 03/04/2008, Alec Matusis <matusis at yahoo.com> wrote:
> I just installed a second webserver machine. About 1/3 of all http requests
>  are now routed to this new webserver, which has identical configuration to
>  the first webserver.
>  Both webservers connect to a single DB server.
>
>  On the new webserver I am intermittently getting the following error:
>  OperationalError: (2003, "Can't connect to MySQL server on '10.18.3.0' (4)")
>
>  What puzzles me is that the old webserver did not have this error under 70%
>  higher request rate (at 600 req/sec), before some of the load was removed
>  from it. Mod_python/python installation is identical on both boxes, and they
>  are running exactly identical scripts. TCP stack also seems to be configured
>  identically.
>  When I got a bunch of these errors, I did notice about 15000 connections to
>  the database in TIME_WAIT state on this problematic new webserver. The new
>  machine is a bit slower (2x2.66GHz xeon vs 2x3.0GHz on the old one), but
>  would this small difference cause such a problem?
>
>  The script that connects to the DB is:
>
>  def load(self):
>        .....
>         dbc = MySQLdb.connect(host=config.db_host, db=config.db,
>  user=config.db_user, passwd=config.db_passwd )
>         dbc.autocommit(True)
>         c = dbc.cursor()
>         r = c.execute( query)
>         if r == 0: #not sure what the key error is supposed to be but it is
>  being caught
>             raise ProfileError
>
>         rvalues = c.fetchone()
>         c.close()
>         dbc.close()
>           ....
>
>
>  I am very puzzled what may cause this...
>
>
>  _______________________________________________
>  Mod_python mailing list
>  Mod_python at modpython.org
>  http://mailman.modpython.org/mailman/listinfo/mod_python
>