According to Dr. Bandwidth, performance analysis has two recurring themes: How fast should this code (or “simple” variations on this code) run on this hardware? If I am analyzing (apparent) performance shortfalls, how can I distinguish between cause and effect? For very simple codes, it may be possible to do… read more
high performance computing
A peculiar throughput limitation on Intel’s Xeon Phi x200 (Knights Landing)
A peculiar throughput limitation on Intel’s Xeon Phi x200 (Knights Landing) Introduction: In December 2017, my colleague Damon McDougall (now at AMD) asked for help in porting the fused multiply-add example code from a Colfax report (https://colfaxresearch.com/skl-avx512/) to the Xeon Phi x200 (Knights Landing) processors here at TACC. There was… read more
SC16 Invited Talk: Memory Bandwidth and System Balance in HPC Systems
I have been involved in HPC for over 30 years: 12 years as student & faculty user in ocean modeling, 12 years as a performance analyst and system architect at SGI, IBM, and AMD, and over 7 years as a research scientist at TACC. This history is based on my… read more