On Wed, 2010-01-27 at 11:22 -0500, Nathan Froyd wrote:


> Also, to reiterate for David Owen, as I must not have been clear, the
> earlier AMD-64 core size was about the same (within 1-2M) of the i386 core
> size.

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 events:

* 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.

* I switched back to AMD-64 when Debian-5 came out. Again, I used their SBCL binary to bootstrap my build of 1.0.34.7. Again, threads were enabled. It was at this point that I noticed the high-seventy Mb sized cores loaded with the web-server.

* While I believe I can recall midpoints - post OS change to 64-bits but pre-upgrade to 1.0.34.7 SBCL - where the core sizes were still in the mid-forties, I have none at this point for evidence and my memory isn't sufficiently accurate to bet money on.

So where there are demonstrable facts, there were actually two variables: an OS change and an SBCL version change.

--Jeff