On Thu, Jan 28, 2010 at 12:10 PM, J. K. Cunningham
> On Wed, 2010-01-27 at 11:22 -0500, Nathan Froyd wrote:
> I find this *very* hard to believe. Just looking at the boinkmarks
> numbers indicates that core files (the base system, without anything
> loaded) have *always* been ~13-15MB larger on x86-64. That disparity
> should remain--and probably will widen--the more stuff you load into
> your core. I can believe your numbers if you were mistakenly
> comparing x86 cores *with* your loaded systems to x86-64 cores
> *without* your loaded systems. But apples-to-apples? No.
> Comparing apples to apples is what I am trying to do, and you may be correct
> that I've omitted some difference. Let me try to reconstruct the sequence of
> * A couple months ago it was running Ubuntu 9.10 -i386 on an AMD-64 machine.
> When I installed that OS I used their SBCL binary to bootstrap my build of
> your latest snapshot at the time (would have been in November). I am sure I
> built that with threads. The size of a core loaded with my webserver was in
> the mid-forty Mb range.
OK, it sounds like you had a 64-bit CPU and a 32-bit OS running on the
machine. Building SBCL would have defaulted to a 32-bit (x86) build,
since you can't run a 64-bit SBCL on a 32-bit OS.
> * I switched back to AMD-64 when Debian-5 came out. Again, I used their SBCL
> binary to bootstrap my build of 22.214.171.124. Again, threads were enabled. It
> was at this point that I noticed the high-seventy Mb sized cores loaded with
> the web-server.
Assuming you mean "switched to a 64-bit OS" when you say "switched
back to AMD-64", then an SBCL built here would be a 64-bit (x86-64)
SBCL. (You could certainly build a 32-bit SBCL for the 64-bit OS, but
it's not the default and requires a bit of fiddling.) You can check
what CPU SBCL is compiled for by using (MACHINE-TYPE).
If I've understood your timeline correctly, then I think you are
comparing apples to oranges wrt core file size. If you wanted to try
building a 32-bit SBCL on your Debian-5 machine and see what that
weighs in at, that would be helpful--and if that still has a 70+ MB
core, then we *do* have a problem. :)