Subject: Processors | September 6, 2016 - 03:05 PM | Ryan Shrout
Tagged: Zen, single thread, geekbench, amd
Over the holiday weekend a leaked Geekbench benchmark result on an engineering sample AMD Zen processor got tech nerds talking. Other than the showcase that AMD presented a couple weeks back using the Blender render engine, the only information we have on performance claims come from AMD touting a "40% IPC increase" over the latest Bulldozer derivative.
The results from Geekbench show performance from a two physical processor system and a total of 64 cores running at 1.44 GHz. Obviously that clock speed is exceptionally low; AMD demoed Summit Ridge running at 3.0 GHz in the showcase mentioned above. But this does give us an interesting data point with which to do some performance extrapolation. If we assume perfect clock speed scaling, we can guess at performance levels that AMD Zen might see at various clocks.
I needed a quick comparison point and found this Geekbench result from a Xeon E7-8857 v2 running at 3.6 GHz. That is an Ivy Bridge based architecture and though the system has 48 cores, we are only going to a look at single threaded results to focus on the IPC story.
Obviously there are a ton of caveats with looking at data like this. It's possible that AMD Zen platform was running in a very sub-optimal condition. It's possible that the BIOS and motherboard weren't fully cache aware (though I would hope that wouldn't be the case this late in the game). It's possible that the Linux OS was somehow holding back performance of the Zen architecture and needs update. There are many reasons why you shouldn't consider this data a final decision yet; but that doesn't make it any less interesting to see.
In the two graphs below I divide the collection of single threaded results from Geekbench into two halves and there are three data points for each benchmark. The blue line represents the Xeon Ivy Bridge processor running at 3.6 GHz. The light green line shows the results from the AMD Zen processor running at 1.44 GHz as reported by Geekbench. The dark green line shows an extrapolated AMD Zen performance result with perfect scaling by frequency.