64 bit VM?

Hello Michael,

preliminary note: I'm not a person able to answer your questions. But I
have some myself...

On 23.04.2006 21:25, Michael Latta wrote:
> What is the status on the 64 bit VM effort?  Is that VM ready for use?
> I am considering a project that Squeak would be good for,

> but I need a
> very large image (20GB-2TB).

Wow!
2TB in RAM?

It would be interesting to hear more about the application...


Regards,
Stephan

--
Stephan Rudlof ([hidden email])
   "Genius doesn't work on an assembly line basis.
    You can't simply say, 'Today I will be brilliant.'"
    -- Kirk, "The Ultimate Computer", stardate 4731.3

On Sun, Apr 23, 2006 at 12:25:43PM -0700, Michael Latta wrote:
> What is the status on the 64 bit VM effort?  Is that VM ready for use?  I am
> considering a project that Squeak would be good for, but I need a very large
> image (20GB-2TB).  Can the garbage collector deal with this?  Is there
> enough locality for the OS virtual memory system to work?  The 64 bit Sun VM
> has been tested with 100s of GB of heap.  Has anything like this been done
> in Squeak?

The short answer would be "no, it's not ready". But it certainly could be made
ready given some motivation and a bit of work.

There was some recent mention of this topic on the vm-dev list. I don't know
if this is archived anywhere, so I'm attaching a copy of the messages.

I don't know how a large object memory will work with respect to garbage
collection etc, but I don't think that anybody has really tried it, so I
would not be inclined to bet on it for a real project just yet. And certainly
I would not expect an image of the size you are describing to be feasible
at this point.

On the other hand, this is a chicken and egg problem. In the absence of
a real project, nobody is likely to really work on 64 bit images and VMs.
So given that this is *your* project, and there are no adverse consequences
to *me* if it does not work out, I say go for it ;)

Dave

Thanks for the follow-up.  In my earlier experience with Squeak I have
noticed that things are not generally finished more than some project
requires.

It sounds like the basic VM is in pretty good shape, but the plug-ins are in
question.  The project I am looking at is server side only so that makes it
easier.

How does Seaside support multiple users in a single OS process?  I assume
that Squeak does not have any multi-processor support yet.

Michael



-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of David T.
Lewis
Sent: Sunday, April 23, 2006 12:58 PM
To: The general-purpose Squeak developers list
Subject: Re: 64 bit VM?

On Sun, Apr 23, 2006 at 12:25:43PM -0700, Michael Latta wrote:
> What is the status on the 64 bit VM effort?  Is that VM ready for use?  I
am
> considering a project that Squeak would be good for, but I need a very
large
> image (20GB-2TB).  Can the garbage collector deal with this?  Is there
> enough locality for the OS virtual memory system to work?  The 64 bit Sun
VM
> has been tested with 100s of GB of heap.  Has anything like this been done
> in Squeak?

The short answer would be "no, it's not ready". But it certainly could be
made
ready given some motivation and a bit of work.

There was some recent mention of this topic on the vm-dev list. I don't know
if this is archived anywhere, so I'm attaching a copy of the messages.

I don't know how a large object memory will work with respect to garbage
collection etc, but I don't think that anybody has really tried it, so I
would not be inclined to bet on it for a real project just yet. And
certainly
I would not expect an image of the size you are describing to be feasible
at this point.

On the other hand, this is a chicken and egg problem. In the absence of
a real project, nobody is likely to really work on 64 bit images and VMs.
So given that this is *your* project, and there are no adverse consequences
to *me* if it does not work out, I say go for it ;)

Dave

On Sun, Apr 23, 2006 at 04:57:22PM -0700, Michael Latta wrote:
> Thanks for the follow-up.  In my earlier experience with Squeak I have
> noticed that things are not generally finished more than some project
> requires.
>
> It sounds like the basic VM is in pretty good shape, but the plug-ins are in
> question.  The project I am looking at is server side only so that makes it
> easier.

Yes, that's right.

> How does Seaside support multiple users in a single OS process?  I assume
> that Squeak does not have any multi-processor support yet.

There is a Seaside mailing list with a number of folks who seem to have
experience with this.

I don't have any experience with it myself, but check out Magma also:
  http://minnow.cc.gatech.edu/squeak/2665
  http://minnow.cc.gatech.edu/squeak/5817

Dave