Re: [Texmacs-dev] disk caches and startup time

[Joris van der Hoeven]

On Tue, 25 May 2004, David Allouche wrote:
> On Tue, May 25, 2004 at 10:24:18AM +0200, Joris van der Hoeven wrote:
> > On Tue, 25 May 2004, Gilles LAMIRAL wrote:
> > > > But what I still don't understand is why TeXmacs
> > > > is so much slower at the *first* time one boots it.
> > >
> > > Because code is already cached in memory.
> >
> > Yes, OK, but why is it so *much* slower compared to other programs.
> > The TeXmacs binary is quite small. Is it the fact that we load many
> > small font, scheme, and other files?
>
> Maybe the file loading patterns are causing a lot of hard disk head
> motion, and that really kills the i/o performance (head motion time is
> measured in miliseconds).
>
> Something to try would be first reading all the relevant texmacs
> files, then all the revelant tex files, then maybe some relevant guile
> files to prime the disk cache. Since the files for a given software
> package are likely to be close to one another on the disk, that might
> end up improving the performance.

We might try to find out first where TeXmacs spends most of its time
in reading files. If someone could profile this for the different
types of files (scheme, tex, encodings, hyphenation, etc.),
then that would be nice.

One thing we might want to do is glue the most frequently used files
together into a big file stored in ~/.TeXmacs/system/...
In that case, we should teach Guile to search files there too, of course.