Open MPI

My new favorite Open MPI mpirun feature: tab completion

2 min read

Today’s guest author is Nathan Hjelm, a Scientist 2 at Los Alamos National Laboratory. We recently added scripts to support tab completion of mpirun flags and run-time MCA configuration variables to the Open MPI trunk development. The scripts support both bash and zsh and have a number of useful features (depending on the shell). Can’t […]

Speaking at Lawrence Berkeley National Lab next week

1 min read

Are you in the Northern California Bay Area and want to hear about Open MPI and/or Cisco’s usNIC technology next week? If so, you’re in luck! I’ll be speaking at Lawrence Berkeley Lab (LBL) next Thursday, November 7, 2013, at 2:30pm.  Click through to see the location and directions and whatnot (LBL requests that you […]

EuroMPI’13 Cisco slides: Open MPI Process Affinity User Interface

1 min read

The slides below are from my presentation at EuroMPI’13 about Open MPI’s flexible process affinity interface (in OMPI 1.7.2 and later).  I described this system in a prior blog entries (one, two, three), but many people keep asking me about it. Josh Hursey from U. Wisconsin, LaCrosse, wrote this IMUDI paper about the interface (IMUDI […]

Short message latency and NUMA effects

2 min read

I’ve previously written a bunch about the effects of location, Location, LOCATION! on MPI applications. Here’s another subtle NUMA effect that a well-tuned MPI implementation can hide from you: intelligently distributing traffic between multiple network interfaces. Yeah, yeah, most MPI implementations have had so-called “multi-rail” support for a long time (i.e., using multiple network interfaces […]

Ultra low latency Ethernet (UCS “usNIC”): questions and answers

4 min read

I have previously written a few details about our upcoming ultra low latency solution for High Performance Computing (HPC).  Since my last blog post, a few of you sent me emails asking for more technical details about it. So let’s just put it all out there.

Open MPI and the MPI-3 MPI_T interface

3 min read

Open MPI recently revamped its entire run-time parameter system (a.k.a., “MCA parameter system”) as part of its implementation effort for the “MPI_T” interface from MPI-3. The MPI_T interface is a standardized interface designed for MPI tools, but can be used by regular MPI application programs, too. Specifically, MPI_T provides programatic access to two types of […]

May 27, 2013

OPEN AT CISCO

Cisco’s Philosophy on Open Source

1 min read

Last weekend, I was fortunate enough to be able to attend the Midwest Open Source Software Conference (MOSSCon 2013).  I met some fascinating people, listened to some great talks, and learned a bunch of new things. All in all, a win. I also presented a talk on two things: The general open source philosophy at […]

MPI and Java: redux

1 min read

In a prior blog entry, I discussed how we are resurrecting a Java interface for MPI in the upcoming v1.7 release of Open MPI. Some users have already experimented with this interface and found it lacking, in at least two ways: Creating datatypes of multi-dimensional arrays doesn’t work because of how Java handles them internally […]

Cisco @SC2012

1 min read

Going to Salt Lake City for Supercomputing 2012 next week?  So are we! Be sure to drop by and see us in the Cisco booth (#2517).  I’ll be there, demonstrating and talking about our latest developments in ultra low latency Ethernet (hint: it includes 250ns port-to-port Ethernet switch latency and our latest MPI/OS-bypass technology on the […]