Subject: Re: Compiler timings on varous MVII NetBSDs etc.
To: None <,>
From: Thor Lancelot Simon <>
List: port-vax
Date: 01/23/2001 13:32:16
On Tue, Jan 23, 2001 at 11:25:11AM -0500, NetBSD Bob wrote:
> Let me say at the outset that I am not trying to put anything about
> NetBSD or any of the BSD freaks down.  My goal in all this is to
> raise issues, and, hopefully, see if they can be resolved to the
> betterment of the entire BSD (including NetBSD and port-vax) crewe.
> Hey, I am a BSD freak in the worst way, too...
> But, I will bite the bullet, and say, ``Houston, we have a problem!''
> This problem is centering around the decided downward trend in
> the usability of NetBSD (particularly 1.5, but also to some extent
> 1.4.x) on older VAX hardware.  I speak particularly to issues of
> bloat and slowness on things like MicroVAX II and 11/7xx machines,
> typically in the 1.0VUP and under class, but, the issues are
> beginning to appear in the MV3100 class machines, and all VAX
> machines with 16mb ram and under.

Let's be clear here:  I strongly believe that the NetBSD kernel got
slower between NetBSD-1.4 and NetBSD-1.5, on all platforms, but that
some changes inordinately impacted the VAX port.  These problems _with
the NetBSD kernel_ should be fixed, as soon as possible.

However, I can't really see the point of complaining about the inclusion
of various bits of userland software.  Yes, gcc is a pig.  However, as
someone who ran an 11/750 with 4.3BSD in production well into the 4.4 era,
I can't complain about it much -- recompiling most of my system's binaries
with GCC (the kernel took a lot more work, and I never did get most of it
to work right if built with GCC) was one of the main hacks I used to keep
the 750 chugging along well beyond its reasonable service life.  Just
rebuilding UUCP and the news software with GCC lowered the machine's
normal load average by about two points.

pcc is a *terrible* compiler.  If we shipped pcc instead of gcc (not that
we can, due to licensing; SCO owns the code) you'd be complaining about
how slowly everything *else* on your system ran, instead of how slowly
the compiler ran.  Your system may be slow now, but if you rebuilt the
world with pcc, it would be a LOT WORSE.

Gcc is not a very good compiler.  On the other hand, it's by far the best
compiler available for the VAX.  It could probably be tweaked to be better,
but I don't know how _much_ better.

It's sensible to pinpoint gcc's memory usage as a problem.  Clearly, newer
gcc versions are worse in this regard than older ones.  On the other hand,
you can always run them with -O1 or -O0; then you will get pcc-like output,
and pcc-like compilation time.  I'm not so sure you want that as you seem
to be, however.