From mlopez at iattc.org  Wed Oct 19 00:37:23 2005
From: mlopez at iattc.org (Milton Lopez)
Date: Tue, 18 Oct 2005 15:37:23 -0700
Subject: [Rd] 64 bit R for Windows
Message-ID: <84B25EE9B4CB1A47A197E6AE76790D7801646334@mail1.lajolla.iattc.org>

One (delayed) follow-up question on this:

We are buying Dell workstations with 64-bit single-core Xeon processors,
and we could add a second processor for not much more. Is it possible to
make a generalized statement as to what kind of performance improvement
we would see with a single vs. dual processors when running R on these
systems?

Thanks again.

M.


-----Original Message-----
From: Thomas Lumley [mailto:tlumley at u.washington.edu] 
Sent: Friday, September 02, 2005 1:29 PM
To: Martin Maechler
Cc: R-devel at r-project.org; Milton Lopez
Subject: Re: [Rd] 64 bit R for Windows

On *Windows* there is an address space limit of about 3Gb (and on 
other 32bit systems)

On a 64bit system the limit is that a vector can't have length greater 
than 2^31, but this would be 8Gb for integers or 16Gb for doubles and so

represents larger objects than you would want to handle on most current 
64-bit systems.

 	-thomas



[Rd] 64 bit R for Windows
Milton Lopez