[Beowulf] re: open64 from AMD (was newbie)

[Mark Hahn]

>> me too, but it brings up a thorny topic: how to compare the
>> performance of different compilers?  the obvious "run it on
>> your code and see" is not helpful in my case, since my goal
>> is to have a good choice for a large shared HPC organization
>> (several thousand users currently.)
>
> Personally I think you're on a hiding to nothing if
> you try to do that,

sorry, but could you decode this 'hiding' thing?  spanking?

> what we do is provide multiple
> compilers and recommend to our users that they test
> their code themselves.

yeah, that's what we say as well - I'm guessing it doesn't work
any better for you as for us ;)

users are lazy, and rightfully so!  for most of them, 
HPC is just a tool, and spending part of their lives 
bumming some cycles doesn't make sense.  it might be different
if we didn't provide free, all-you-can-eat cycles...

I still think it's a useful question.  even if the answer is that
different compilers/switches only make 5% difference, that's 
useful to know...

> Not a direct answer I'm afraid, but just wanted to
> share our experiences (we've got a 600+ registered
> users at present, but they're not all active at once
> thankfully).

we're up to 3300 users, >300 active at any time...