[Beowulf] Gentoo in the HPC environment

[Matt Wallis]

On 01/07/14 13:45, Jonathan Aquilina wrote:
> This question probably sounds like a stupid one, but what difference in an
> HPC environment and to parallel written code does compiler version make?

Depends on the day of the week, the processor, the code, and your 
cluster really.

Sometimes code from GCC is faster, sometimes code from the Intel 
compiler is faster.
Some people write code that only compiles with the Intel compiler, or 
link against libraries distributed with the compiler.

Then of course you might have a BlueGene with PPC cores rather than x86, 
and while the difference in performance between GCC for PPC and the IBM 
XL compilers is slight these days, it wasn't always the case.

Intel also distributes highly tuned versions of some maths libraries 
with their compilers, and libraries designed for offloading work to the 
the Xeon Phi, without recompiling the application.

And then when it comes time to debug why the application doesn't work, 
commercial compiler suites often come with very good debugging tools.

Matt.

-- 
Matt Wallis
mattw at madmonks.org