From: Drew Eckhardt (drew@caesar.cs.colorado.edu)
Date: 06/28/93


From: drew@caesar.cs.colorado.edu (Drew Eckhardt)
Subject: Re: Linux performance: OUCH!
Date: Mon, 28 Jun 1993 06:41:49 GMT

In article <C96oC5.366@inviso.com> gilbert@inviso.com (Gilbert Callaghan) writes:
>It is on a local network with several other 486/33's running Interactive
>Unix. It's running 0.99pl10 with net-2 and everything works great.
>
> BUT... IT'S SLOW!!!
>
>Here are comparisons of Linux and ISC compiling MicroEMACS with gcc.
>This is the output of 'time make':
>
> Linux ISC
>
> real 8:34.0 real 2:37.1
> user 8:07.1 user 1:23.5
> sys 20.4 sys 11.6
>
>The fact that the 'sys' time is low on both systems makes me think
>that this may not be a linux OS problem (I hope).

It's not, it's a GCC problem. GCC generates incredibly tight
code that's also correct on an incredible variety of platforms.
Unfortunately, it does this at the expense of compilation time,
and I have yet to see a vendor supplied 'C' compiler that's
slower (I administer machines running HPUX, Irix, Ultrix,
AIX, and various BSD flavors).

>Oh, they both have at least 32 meg RAM.
>
>Is there something wrong with my system, or is Linux just a dog?

The 'C' compiler isn't really part of Linux itself per se, I
imagine that you'll see Linux in front if you use GCC under
ISC.

>Any comments you have experienced concerning linux' performance, or
>suggestions on how to fix this (if it's a problem with my system) are
>greatly appreciated.

I think you'll find that X performance, etc under Linux on the
same hardware will be much better, especially on smaller systems
where Linux's fully unified buffer cache, etc can really help.

Personally, since I only compile my applications once,
I'll trade them running faster for the 'C' compiler running
slower.

As far as development - it's still fast enough :-)

GCC will never be faster, if you really want to do something about
it please consider writing your own 'C' compiler (removing the separate
preprocessing step and doing a hand coded scanner can really help
performance!) or helping out with the iBCS (ie, SVR2/33) or iABI (SVR4)
binary compatability projects which would let you run a different compiler.

-- 
Boycott USL/Novell for their absurd anti-BSDI lawsuit. | 
Condemn Colorado for Amendment Two.                    | Drew Eckhardt
Use Linux, the fast, flexible, and free 386 unix       | drew@cs.Colorado.EDU 
Will administer Unix for food                          |