LFS-BOOK-3.2-RC1 - minor correction and suggestions

Matthias Benkmann matthias at winterdrache.de
Thu Feb 14 12:36:36 PST 2002

On Wed, 13 Feb 2002 11:08:11 -0500 Gerard Beekmans
<gerard at linuxfromscratch.org> wrote:

> On Wed, Feb 13, 2002 at 02:10:04AM +0100, Matthias Benkmann wrote:
> > This means that for 140ms more time you gain 830K more memory. So
> > every time you say one-one-hundred you earn 8MB of RAM. That sounds
> > like a good deal to me :-) A little bit more scientifically:
> > A 3.4% increase in running time buys you a reduction of RSS by 29%.
> So --without-gnu-malloc is better for the system resources wise if you
> do extreme things. I thing the average user wouldn't have a need for
> such long loops so I'm wondering how this differs for average day-to-day
> use, say running all the bootscripts.

For the boot scripts this doesn't matter. They spend most of their time
calling other programs and don't do much with shell variables. The same is
true for most scripts IMHO. If you really care about speed and resources
regarding scripts, using a different shell as sh (ash for instance) is
going to give you MUCH better results than any kind of bash optimization.
I think we should focus on interactive bash processes for our decision,
because they stay around for a long time. Here I think using
--without-gnu-malloc is a good idea. They run for hours so minimizing
resource usage is a good idea, and interactive shells do not need speed
because the human is the limiting factor. Personally I have added
--without-gnu-malloc to my build script. But the effects are small, so
that I think either way is okay for LFS. 

But please, Gerard, don't add a paragraph telling people they could use it
or may decide to not use it if blablabla. This creates more confusion than
this issue is worth. Either add the switch with a small sentence like
"--without-gnu-malloc: use standard glibc malloc optimized for low
resource usage" or just pretend this discussion has never come up. Do NOT
under any circumstances use the magic word "speed" (or related words such
as "faster" and "slower") anywhere in the explanation or we'll end up
discussing this issue over and over.


Black holes are where God divided by zero.

Unsubscribe: send email to listar at linuxfromscratch.org
and put 'unsubscribe lfs-dev' in the subject header of the message

More information about the lfs-dev mailing list