Top 500 supers - rise of the Linux quad-cores

SC09 Looking at the semi-annual Top 500 list of supercomputers, you would never know the world was battling recession. Supercomputer centers keep chucking out old tech and rolling in new tech at the same feverish pace.

The fall edition of the list was announced this morning at the SC09 supercomputing trade show in Portland, Oregon. The single biggest transition in the list is the move to quad-core - and in some notable cases, six-core - processors inside supercomputing systems. And most of the machines on the list now run Linux with x64 processors.

The key differences between machines are what network interconnects and topologies are deployed and what adjunct processing elements (if any) are used to boost the performance of the central processors in server nodes. The differences are substantial enough for specific workloads to keep a whole bunch of HPC suppliers busy at a time in the market when you think there might be two suppliers left.

According to the techies who put together the Top 500 rankings - Hans Meuer of the University of Mannheim, Germany; Erich Strohmaier and Horst Simon of Lawrence Berkeley National Laboratory; and Jack Dongarra of the University of Tennessee - there are 427 machines that have quad-core processors. Intel's "Nehalem-EP" Xeon 5500 processors have tripled their presence on the Top 500 list, to 95 machines, up from 33 in the June 2009 rankings and zip in the November 2008 rankings because the Xeon 5500s came a little later than expected to market in March of this year. (El Reg detailed those two prior Top500 lists here and there).

Intel is the main chip supplier in 402 of the 500 machines that made the cut this time around, and 380 of those are using quad-core processors of one generation or another. Unlike AMD's current line of quad-core "Shanghai" and six-core "Istanbul" processors, which plug into existing Rev F system boards, Intel's Xeon 5500s require a box swap from the prior Xeon 5300 "Clovertown" and Xeon 5400 "Harpertown" series.

There are 42 machines on the list using AMD's processors and 52 using IBM's Power processors, both losing a little ground since the June 2009 ranking. Dual-core processors are still in use on 59 machines (all of the Power5 and Power6 supers on the list are using dual-core chips), and there are only four machines that employ single-core processors in their cluster nodes.

But AMD is still pretty pumped, and for a number of reasons. First of all, after trying to outrun IBM's hybrid "Roadrunner" Opteron-Cell massively parallel blade server at Los Alamos National Laboratory for the past several lists, the "Jaguar" all-Opteron XT5 box made by Cray and installed at Oak Ridge National Laboratory has pounced upon Roadrunner and pulled out some flesh and spit out some feathers.