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

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 is a sub-workshop of EuroMPI focusing on end-user issues) to get a little more publicity and awareness of this process affinity system.  Specifically, we designed this affinity system so that we could get feedback from real end users about what is useful and what is not.

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Short message latency and NUMA effects

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 for MPI traffic).  But there’s more to it than that.

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

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.

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Open MPI and the MPI-3 MPI_T interface

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 MPI implementation data:

  1. Control variables: used to control the behavior of an MPI implementation
  2. Performance variables: provide access to internal MPI implementation performance metrics

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Cisco’s Philosophy on Open Source

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:

  1. The general open source philosophy at Cisco
  2. My specific open source work at Cisco

The slides that I presented are below (slightly edited from their original form; I used a few animations in my original slides, which don’t work on Slideshare):
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