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From: schoch@sheba.arc.nasa.gov (Steve Schoch)
Newsgroups: comp.windows.x
Subject: Re:  Short circuiting network communication
Message-ID: <1990Dec10.181808.1528@news.arc.nasa.gov>
Date: 10 Dec 90 18:18:08 GMT
References: <9012091641.AA14521@Larry.McRCIM.McGill.EDU>
Sender: usenet@news.arc.nasa.gov (USENET Administration)
Reply-To: schoch@trident.arc.nasa.gov (Steve Schoch)
Organization: NASA Ames Research Center, Moffett Field, CA
Lines: 15

|> > (1) When server and client are resident on the same machine, is there
|> >     a reasonable way to NOT pass messages over the net, but directly
|> >     (e.g. memory-to-memory ??) to enhance performance ?

If your $DISPLAY is unix:0 or :0 the communication will be over UNIX domain
sockets which means that the data will not go through TCP.  UNIX domain
sockets are basically the same as pipes once they are connected.

Of course, this still means that requests will take about 2 memory copies
to get from client to server (one from client memory to kernel memory and
one from kernel memory to server memory).  However, using TCP also gives
the overhead of window-size calculations, checksum verification, IP address
checking, etc.

	Steve