AMD Piledriver
 

Does anyone have access to a Piledriver system? I have a friend who needs to run some benchmarks. Any help would be appreciated.

My wife's computer has an A10-5700 Trinity APU. It's running Window 7 x64, but I could boot a Ubuntu live cd while she's not looking if necessary. :smile:

And that is how I learned what a Piledriver is... :blush:

[QUOTE=frmky;318679]My wife's computer has an A10-5700 Trinity APU. It's running Window 7 x64,[/QUOTE]

That will be perfect - thanks!

[QUOTE=LaurV;318680]And that is how I learned what a Piledriver is... :blush:[/QUOTE]
"Obviously you're not a golfer!"
Or a fan of Andy Kaufman!

Is it worth using avx code on piledriver? Have they improved it since bulldozer?

[QUOTE=henryzz;318767]Is it worth using avx code on piledriver? Have they improved it since bulldozer?[/QUOTE]

From the articles I've read, SSE2 code will be faster on Bulldozer and Piledriver

[QUOTE=Prime95;318787]From the articles I've read, SSE2 code will be faster on Bulldozer and Piledriver[/QUOTE]

..damn, was hoping they would improve AVX on piledriver, oh well :smile:

Thank you.
 

[QUOTE=frmky;318679]My wife's computer has an A10-5700 Trinity APU. It's running Window 7 x64. :smile:[/QUOTE]
Thanks from me, too. I'm the friend that George was referring to.

[QUOTE=henryzz;318767]Is it worth using avx code on piledriver? Have they improved it since bulldozer?[/QUOTE]
I've been analyzing Bullzoder performance for a while and I'm now going to see how much of it applies to Piledriver.
Bulldozer has a family of 15h and models between 00h and 0fh.
The one Piledriver system I've seen (an A8 which has Piledriver cores) has a family of 15h and model of 10h. I'm guessing that models 10h - 1fh are for Piledrivers.
The Software Optimization Guide for family 15h shows different timings for some instructions, but otherwise the microarchitecture seems to be the same.
There are pipeline differences with models 20h to 2fh. I'm guessing that these are for Steamroller cores, but that's just a guess.

Regarding using AVX instructions... My opinion is that there is no performance advantage to using AVX 128 bit instructions over the legacy instructions. The AVX may save slightly on code space.
AVX 256 bit instructions will definitely save on code space. Also, you won't run out of YMM registers as fast as XMM registers. Instruction timings for a 256 bit instruction are generally double those for the 128 bit instructions.
Some AVX 256 bit code may run a bit slower than equivalent 128 bit code, particularly stores to memory.
So my own recommendation is to stick to 128 bit AVX, or legacy instructions, unless you are running out of registers. Or try it both ways and see which way comes out better.

Another thing about Bulldozer / Piledriver. The best way to get the full performance out of a module is if both of the module's cores are running similar workloads. A program running in a core with the other core idle tends to get significantly less throughput in the decoding stage, in the loads and stores. Also, depending on the time it takes instructions to retire, it is more likely that the retire buffer will fill up and stall the processor.

[QUOTE=mrolle;318902]
The one Piledriver system I've seen (an A8 which has Piledriver cores) has a family of 15h and model of 10h. I'm guessing that models 10h - 1fh are for Piledrivers.
[/QUOTE]
My wife's is also family 15h, model 10h. Attached is the screenshot from CPU-Z.