Path: utzoo!attcan!uunet!mailrus!ncar!boulder!stan!ninja!toml
From: toml@ninja.Solbourne.COM (Tom LaStrange)
Newsgroups: comp.windows.x
Subject: Re: window manager traffic
Message-ID: <1990May30.155534.24497@Solbourne.COM>
Date: 30 May 90 15:55:34 GMT
Sender: news@Solbourne.COM
Organization: Solbourne Computer, Inc.
Lines: 35

> 	I've been doing some measurements of packets from my NCD X terminal.
> Various window managers seem to generate enormous amounts of traffic for
> common operations.  Popping up a menu or placing a window causes the NCD to
> generate packtes as fast as it can, about 300 packets/s.  I realize that
> this comes from X's workstation heritage, where WM traffic was just memory
> copies.
>	 Does anyone know how to (or plan to) reduce this traffic?  On our
> large network, it's possible for WM traffic to take up a large chunk of
> network bandwidth.
>	 DEC may have done the right with their new X terminal by putting the
> WM in the server.  Do any other manufacturers (especially NCD) plan to do
> this?  It would probably be better to have multiple loadable WM's, but I'm
> sure we could live with a single hardcoded one.

Much of the network traffic is due to historical reasons.  Older workstations
such as the Vaxstation I and II were not fast enough to supply the WM with
MotionNotify events sufficient to keep move/resize outlines tracking
the mouse.  Because of this, some window managers will send off QueryPointer
requests rather than letting the server supply MotionNotify events.  This
makes performance look much better on slower workstations.

Several people have mentioned that this is a "bug" and should be fixed.  My 
how times change, the first versions of twm used MotionNotify events until
I got a "bug" fix that implemented the QueryPointer stuff.  Since no one
out there is using a slow workstation, prehaps we should change it back :-)

BTW, NCR also has the capability to put clients such as the WM into the 
terminal.

--
Tom LaStrange

Solbourne Computer Inc.    ARPA: toml@Solbourne.COM
1900 Pike Rd.              UUCP: ...!{boulder,sun}!stan!toml
Longmont, CO  80501