Subject: Re: X server as a Unix system process
To: Bill Sommerfeld <>
From: Jukka Marin <>
List: tech-kern
Date: 07/15/1997 08:17:11
On Mon, Jul 14, 1997 at 07:39:15PM -0400, Bill Sommerfeld wrote:
> It's worth noting that Jim Gettys and Bob Scheiffler sweated bullets
> in order to minimise the number of round-trips in the X protocol.  in
> particular, the protocol is asynchronous; graphics requests are
> buffered and sent over to the server in decent-sized batches.  You
> don't do one IPC per line or text string...

This brings my Applixware problem into my mind again.  Using ktrace, I
found out that Applixware (the linux version on i386) is doing lots of
small reads and writes to the X socket.  After a write, it calls
oldselect() which takes 50 ms to return.  A word processor screen update
consists of a thousand (well, it sure looks like that) write/oldselect/read
chunks of code, most of which take 50 ms.. so the screen update takes 15
seconds or more.  This only happens after Applixware has been running for
a while.  Any new ideas, anyone? :)

I'd like to add some debug printf()s in the oldselect() code, but the
amount of data would flood the logs immediately :-/



                       1503 kHz @ 22:30 EET DST Mon-Fri

                     ---> <---