Cisco Blogs


Cisco Blog > High Performance Computing Networking

MPI run-time at large scale

June 28, 2011 at 5:00 am PST

With the news that Open MPI is being used on the K supercomputer (i.e., the #1 machine on the June 2011 Top500 list), another colleague of mine, Ralph Castain — who focuses on the run-time system in Open MPI — pointed out that K has over 80,000 processors (over 640K cores!).  That’s ginormous.

He was musing to me that it would be fascinating to see some of K’s run-time data for what most people don’t consider too interesting / sexy: MPI job launch performance.

For example, another public use of Open MPI is on Los Alamos National Lab’s RoadRunner, which has 3,000+ nodes at 4 processes per node (remember RoadRunner?  It was #1 for a while, too).

It’s worth noting that Open MPI starts up full-scale jobs on RoadRunner — meaning that all processes complete MPI_INIT — in less than 1 minute.

Read More »

Tags: , , ,

Open MPI powers 8 petaflops

June 25, 2011 at 6:20 pm PST

A huge congratulations goes goes out to the RIKEN Advanced Institute for Computational Science and Fujitsu teams who saw the K supercomputer achieve over 8 petaflops in the June 2011 Top500 list, published this past week.

8 petaflops absolutely demolishes the prior record of about 2.5 petaflops.  Well done!

A sharp-eyed user pointed out the fact that Open MPI was referenced in the “Programming on K Computer” Fujitsu slides (which is part of the overall SC10 Presentation Download Fujitsu site).  I pinged my Fujitsu colleague on the MPI Forum, Shinji Sumimoto, to ask for a few more details — does K actually use Open MPI with some customizations for their specialized network?  And did Open MPI power the 8 petaflop runs at an amazing 93% efficiency?

Read More »

Tags: , , ,

X petaflops, where X>1

October 29, 2010 at 4:49 am PST

Lotsa news coming out in the ramp-up to SC.  Probably the biggest is that about China being the proud owners of the 2.5-petaflop computing monster named “Tianhe-1A”.

Congratulations to all involved!  2.5 petaflops is an enormous achievement.

Just to put this in perspective, there are only three other (publicly disclosed) machines in the world right now that have reached a petaflop: the Oak Ridge US Department of Energy (DoE) “Jaguar” machine hit 1.7 petaflops, China’s “Nebulae” hit 1.3 petaflops, and the Los Alamos US DoE “Roadrunner” machine hit 1.0 petaflops.

While petaflop-and-beyond may stay firmly in the bleeding-edge research domain for quite some time, I’m sure we’ll see more machines of this class over the next few years.   Read More »

Tags: , , ,