Mark Roulo (markroulo.delete@this.yahoo.com) on February 5, 2013 8:40 am wrote:
> Michael S (already5chosen.delete@this.yahoo.com) on February 5, 2013 2:51 am wrote:
> > After you ported to Linux/x64, shouldn't porting to Linux/IPF be close
> > to "just recompile"? Esp, if the same code already runs on SPARC?
>
> This is only an option when you have the source.
>

Richard had the source.

> If your system needs a binary that hasn't been compiled for the new architecture:
>
>     *) For x86 to x64 you can keep running the 32-bit binary
>
>     *) For x86 to ia64 you are kinda done

IA32EL should be good enough for non-performance-critical 3rd-party binaries. They claimed 50% of native speed, which is pretty impressive.

>
> Which makes it harder for people to migrate gradually.
>
> Which causes fewer people to migrate.
>
> Which lessens the obvious demand for the 3rd party to port to ia64.
>
> There is nothing new here and my company is seeing the same thing with respect to Xeon
> Phi (which is only x86 for scalar code) ... no SSE support, so we can't move gradually.
> It will be an all or nothing move, which probably means nothing. AVX2 in Haswell
> we *will* support gradually and all the old SSE code will continue to run.

That is your only problem with Xeon Phi? Do your apps have 4000-way parallelism (or 2000-way for double-precision) readily available?

In what I am doing right now 100-way data parallelism is easy to find, 400-way would be hard, 4000-way - impossible without huge rethink.