Help with theoretical crazyness, please!

[Michael Wittman]

On Wed, Nov 14, 2001 at 01:48:49PM -0700, Brian Cluff wrote:
> Ok, I'm still struggling with these P100 machines that I am trying to run
> Star Office on.  The problem is that under windows SO loads in 1 min or
> less, but it's not stable.  Under linux it takes over 5 min to load, but is
> stable, but by the time it's done loading the class is partially over, so
> it's unacceptable... and no it's not a lack of memory problem.
> 
> Anyway, in a dream last night I though it something that is so sick and
> twisted it might just work, but I don't know how to do it.
> a while ago I heard of a way to "compile" perl programs by causeing a core
> dump and then executing that core dump as a binary executable.   I was
> thinking that if I could do the same thing with SO that I could load the
> whole thing on these slow machines in about 10 seconds.. beating windows by
> a lot.
> 
> If anyone has any ideas how I could do this it would help me convert the
> school a lot easier.

If the limiting factor is the processor speed, there's probably not much
you can do about it.  However, if the limiting factor is the speed of
reading files from disk, you may be able to speed things up by doing
some intelligent prefetching of files to the disk cache.  There was a
"preload" application and kernel module that used this technique, but
unfortunately it's unmaintained alpha code that hasn't been updated in
a while (the kernel module is for 2.0.x!).  You should be able to do
something equivalent with shell scripts though.

You can see whether prefetching files would help by loading Star Office,
quitting, then immediately loading it again.  If the second load is
significantly faster than the first, then this tecnique should work for
you.  Let me know and I'll try to work up some scripts that you could use.

-Mike