Path: utzoo!attcan!uunet!wuarchive!decwrl!shelby!portia!name
From: name@portia.Stanford.EDU (tony cooper)
Newsgroups: comp.windows.x
Subject: The easiest way to speed up X11R4
Message-ID: <8968@portia.Stanford.EDU>
Date: 8 Feb 90 10:57:53 GMT
Sender: tony cooper <name@portia.stanford.edu>
Organization: Stanford University
Lines: 32

Suppose I wanted to spend, say, a day making X11R4 faster for my
particular hardware. What would be the best way to spend my time?
I am interested in 8 bit color speedups at the expense of portability.

For example:

Is there a piece of code that is executed everytime the server
does something? I could convert it to assembly language.

Is there some device-independent code that could be converted to
device-dependent code?

The README for the cfb directory says the cfb code is "very slow".
Is the cfb directory a good place to start? Which are the 20 most
time-critical lines?

Which are the 20 most time-critical lines in the whole of X11R4?

I have done this sort of thing before with spectacular results. I
once sped up a program an order of magnitude by changing one line
of C code inside a loop into assembly language and using registers.
It seems to me that X11 has a lot of potential for this kind of
speedup since it is so device independent and since all graphics
operations boil down to just the simple turning on or off bits.
There must be some code somewhere that does the nitty gritty bitty
stuff at a low level that I can get at.

For those interested in receiving a copy, I'll be doing this for
the MC68030. Even more specifically, it will be for the Macintosh II.

Tony Cooper
tony@popserver.stanford.edu