[Python-bugs-list] [ python-Bugs-774751 ] slow socket binding & netinfo lookups

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Bugs item #774751, was opened at 2003-07-21 01:57
Message generated for change (Comment added) made by jackjansen
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Category: Macintosh
Group: Python 2.3
Status: Open
Resolution: None
Priority: 5
Submitted By: Stuart Bishop (zenzen)
>Assigned to: Skip Montanaro (montanaro)
Summary: slow socket binding & netinfo lookups

Initial Comment:
The following code takes < 1 second to run under Python 
2.1, but 20 seconds to run under Python 2.2 or 2.3 on a top-
end PowerBook running OSX 10.2. It is part of the Zope 
startup routine.

def max_server_sockets():
    sl = []
    while 1:
        try:
            s = socket.socket (socket.AF_INET, 
socket.SOCK_STREAM)
            s.bind (('',0))
            s.listen(5)
            sl.append (s)
        except:
            break
    num = len(sl)
    for s in sl:
        s.close()
    del sl
    return num



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>Comment By: Jack Jansen (jackjansen)
Date: 2003-07-21 22:52

Message:
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I have absolutely nothing to contribute wrt. this bug. As Just is 
away I guess Skip is the best target for the hot patato. 

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Comment By: Skip Montanaro (montanaro)
Date: 2003-07-21 18:33

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Digging a bit deeper, it appears on Mac OS X that
fake_getaddrinfo is used.  That's deemed not to be thread-safe.
I see three static or global variables acessed by this function:

    firsttime - simple guard
    translate - set inside the guard - readonly after that
    faith_prefix - same

Why not push the guard and initialization code into init_socket
and protect it with the getaddrinfo lock?  Fake_getaddrinfo
would thus be thread-safe and could be accessed without
acquiring a lock.


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Comment By: Skip Montanaro (montanaro)
Date: 2003-07-21 18:14

Message:
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whoops...  my apologies for not posting here.


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Comment By: Tim Peters (tim_one)
Date: 2003-07-21 17:50

Message:
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Attaching copious info from Skip Montanaro (skip.txt).

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Comment By: Anthony Baxter (anthonybaxter)
Date: 2003-07-21 09:05

Message:
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Is this something that should be looked at for 2.3rc2?


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