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Subject: Re: [OMPI users] Issues on install 1.3.1
From: Iain Bason (Iain.Bason_at_[hidden])
Date: 2009-04-02 21:14:21


On Apr 2, 2009, at 2:45 PM, Gus Correa wrote:

> Sorry, I don't have an answer about performance.
> You may need to ask somebody else or google around
> about the relative performance of 32-bit vs. 64-bit mode.

It is worth trying 64-bit. The performance is going to depend on the
program. Since 64 bit pointers take more cache space, a program that
uses a lot of pointers will run more slowly. However, the x64
architecture has more registers than the x86 architecture, and that
can make a 64 bit program run faster. Overall, it is probably more
common for program to run faster in 64 bit mode, but your program
could be in the minority.

Iain