Re: [Caml-list] A small footprint GUI for OCaml

[Eric Cooper <ecc@cmu.edu>]

On Sat, May 26, 2007 at 03:09:43PM -0700, Alexsandro Soares wrote:
> My collaborators and I wrote a small footprint graphics.cmxa based
> GUI for OCaml.  It works well on Windows, but not so well on
> Linux. In fact, in most Linux installations the program turns out to
> be unbearably slow; to make it usable, I am forced to use powerful
> and well tuned video cards.

I tried your program briefly and noticed (using a load monitor) that
it was constantly using CPU cycles even when it should be idle.  So I
ran it under "strace" and saw that it was continually reading data
from the connection to the X server.  This occurs inside a signal
action, probably triggered by a timer interrupt.

Compare that to a real Emacs process, which is almost always in a
blocking select() system call when idle.

I haven't looked at your source code, or the Graphics implementation,
but I conclude that you need to find a way to block, rather than poll,
for input events.

-- 
Eric Cooper             e c c @ c m u . e d u