On Tue, 2005-07-12 at 13:24, Mohan, Ross wrote:
> From AMD's suit against Intel. Perhaps relevant to some PG/AMD issues.
>
> "...125. Intel has designed its compiler purposely to degrade performance when a program
> is run on an AMD platform. To achieve this, Intel designed the compiler to compile code
> along several alternate code paths. Some paths are executed when the program runs on an Intel
> platform and others are executed when the program is operated on a computer with an AMD
> microprocessor. (The choice of code path is determined when the program is started, using a
> feature known as "CPUID" which identifies the computer's microprocessor.) By design, the
> code paths were not created equally. If the program detects a "Genuine Intel" microprocessor,
> it executes a fully optimized code path and operates with the maximum efficiency. However,
> if the program detects an "Authentic AMD" microprocessor, it executes a different code path
> that will degrade the program's performance or cause it to crash..."
Well, this is, right now, just AMD's supposition about Intel's
behaviour, I'm not sure one way or the other if Intel IS doing this.
Being a big, money hungry company, I wouldn't be surprised if they are,
but I don't think it would affect postgresql for most people, since they
would be using the gcc compiler.
