On Fri, Oct 29, 2010 at 09:48:11AM +0200, Bert Freudenberg wrote:
> On 29.10.2010, at 06:25, Dan Ingalls wrote:
> 
> > Hi Guys ;-)
> > 
> > Anyone have experience with running super huge Squeaks?  I have the chance to use an absurdly big machine.  I'd appreciate advice (offline unless you think it would be generally useful) regarding the relative stability of, say, linux and windoze builds of 64-bit Squeaks known (or thought) to run with over a terabyte of objects, and also where there may be some pre-built 64-bit images (sorry if this is in an obvious place).  Finally (since I've mainly used a Mac for Squeak) I guess I'll have to know how to tell it how big to be, or would it grow gracefully if I just said "(String new: 1000000000000) size" in a normal image?
> > 
> > Thanks
> > 
> > 	- Dan
> 
> Dave Lewis has been working on 64 bit stuff, he surely will respond (and please keep responses on list, this is rather interesting). A recent image is here:
> 
> 	http://squeakvm.org/squeak64/sq64-dtl.zip
> 
> I think there isn't even much experience with a Gigabyte-sized image ...

Hi Dan,

The image that Bert mentions is an updated version of your original
64-bit image, suitable for running on a current Squeak VM. I have
not tried tracing the latest Squeak trunk image (sounds like a good
project for this weekend though :)

The quickest way to get a VM running is to start with an up to
date Squeak image, load latest VMMaker from www.squeaksource.com/VMMaker
and platform sources from Subversion. The "64-bit VM" button is
gone from the VMMaker tool, all that is needed to build the 64 bit
version is to set a macro either in ./build/config.h or in
./src/vm/interp.h:

  #define SQ_VI_BYTES_PER_WORD 4

I use Linux for running this stuff, so I can't speak to Windows or
OS X. On a unix platform, if you evaluate "(String new: 1000000000000) size"
in sq64-dtl.image, you will get a low space notifier. I remember adding
some checks to the VM to prevent address overflows for allocations
that are "unreasonably large), and I think this notifier reflects
hitting that limit (sorry I can't recall the details, I'll check later).
It would be fun to see how big "unreasonably large" could be though :)

A gigabyte is no problem though. The following succeeds on a
64-bit image:

  (String new: 1000000000) size ==> 1000000000

For allocation requests that are within the current VM limits,
what you can expect to see on a unix box is that your VM will
cheerfully keep allocating memory from the OS until your system
starts swapping pages to disk, at which point everything on the
system slows to a crawl. It will be interesting to see what happens
on a really big box with lots of memory.

Dave