Node-Level Performance Engineering

This course covers performance engineering approaches on the compute node level. Even application developers who are fluent in OpenMP and MPI often lack a good grasp of how much performance could at best be achieved by their code. This is because parallelism takes us only half the way to good performance. Even worse, slow serial code tends to scale very well, hiding the fact that resources are wasted. This course conveys the required knowledge to develop a thorough understanding of the interactions between software and hardware. This process must start at the core, socket, and node level, where the code gets executed that does the actual computational work. We introduce the basic architectural features and bottlenecks of modern processors and compute nodes. Pipelining, SIMD, superscalarity, caches, memory interfaces, ccNUMA, etc., are covered. A cornerstone of node-level performance analysis is the Roofline model, which is introduced in due detail and applied to various examples from computational science. We also show how simple software tools can be used to acquire knowledge about the system, run code in a reproducible way, and validate hypotheses about resource consumption. Finally, once the architectural requirements of a code are understood and correlated with performance measurements, the potential benefit of code changes can often be predicted, replacing hope-for-the-best optimizations by a scientific process.

This course provides - via lectures, demos, and hands-on labs - scientific training in Computational Science, and in addition, the scientific exchange of the participants among themselves.

 

Location

Online course
Organizer: HLRS, University of Stuttgart, Germany

Start date

Jun 18, 2024
08:45

End date

Jun 21, 2024
13:00

Language

English

Entry level

Advanced

Course subject areas

Performance Optimization & Debugging

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Prerequisites and content levels

Prerequisites:
  • Familiarity with Linux and Linux editors is recommended.
  • Basics/principles of programming in C or Fortran and basic OpenMP.
Content levels:
  • Intermediate: 8 hours 15 minutes
  • Advanced: 8 hours 15 minutes
  • Community: 2 hours 45 minutes

Learn more about course curricula and content levels.

Instructors

Dr. habil. Georg Hager and Dr.-Ing. Jan Eitzinger  (NHR@FAU, Friedrich-Alexander-Universität Erlangen-Nürnberg)
Bert Wesarg (ZIH Uni. Dresden) for the tools-day

Agenda

- preliminary -

Day 1 (Tue, June 18)

  • 08:45   Enter the Zoom meeting
  • 09:00   Welcome – Intro
  • 09:30   Computer architecture for software developers part 1
  • 10:15   Coffee break
  • 10:30   Computer architecture for software developers part 2
  • 10:45   Hands-on: Divide benchmark
  • 11:30   Tools: Topology and affinity, frequency
  • 12:00   Lunch
  • 13:00   Hands-On: topology, affinity
  • 13:45   Introduction to the Roofline Model
  • 15:00   Coffee break
  • 15:15   Quiz/Q&A/open end

Day 2 (Wed, June 19)

  • 08:45   Enter the Zoom meeting
  • 09:00   Tools: Performance counters
  • 09:45   Hands-on: performance counters and memory bandwidth
  • 10:30   Coffee break
  • 10:45   Roofline case study: stencils
  • 11:30   Performance Engineering: Basic skills
  • 12:15   Lunch
  • 13:15   Hands-on: Dense matrix-vector multiplication (I)
  • 13:45   Optimal use of parallel resources:  ccNUMA
  • 14:15   Hands-on: Dense matrix-vector multiplication (II)
  • 14:45   Roofline case study: Tall & skinny matrix-matrix multiplication
  • 15:15   Coffee break
  • 15:30   Quiz/Q&A/open end

Day 3 (Thu, June 20)

  • 08:45   Enter the Zoom meeting
  • 10:00   Hands-on: SIMD in MiniMD
  • 11:00   Coffee break
  • 11:15   Roofline case study: Sparse matrix-vector multiplication
  • 12:15   Lunch
  • 13:15   Hands-on: Matrix-free CG solver
  • 14:45   Coffee break
  • 15:00   The ECM performance model
  • 16:00   Quiz/Q&A/open end

Day 4 (Fri, June 21: Tools Day)

  • 08:45   Enter the Zoom meeting
  • 09:00   Performance engineering from the application point of view
  • 09:30   Monitoring with Score-P
  • 09:45   Hands-on: MiniMD with Score-P
  • 10:15   Coffee break
  • 10:30   Profile exploration and measurement scoring
  • 10:45   Trace exploration with Vampir
  • 11:15   Coffee break
  • 11:30   Hands-on: Load imbalance: SpMV
  • 12:15   Wrap-up

 

Handouts

Before the course, the course material and an updated agenda will be available here.

An older version of this course with most of the material (including the audio information) can also be viewed in the online self-study materials.

Registration information

Register via the button at the top of this page (will be available soon).

Registration due to May 19, 2024.
Late registrations after this date are still possible according to the course capacity, maybe with reduced quality of the service.

Fees

  • Students without master’s degree or equivalent: 32.50 Euro
  • PhD students or employees at a German university or public research institute: 67.50 Euro
  • PhD students or employees at a university or public research institute in an EU, EU-associated or PRACE country other than Germany: 135 Euro
  • PhD students or employees at a university or public research institute outside of EU, EU-associated or PRACE countries: 270 Euro
  • Other participants, e.g., from industry, other public service providers, or government: 690 Euro

 

Link to the EU and EU-associated (Horizon Europe), and PRACE countries.

Our course fees include coffee breaks (in classroom courses only).

Contact

Lucienne Dettki, phone 0711 685 63894, lucienne.dettki(at)hlrs.de

HLRS Training Collaborations in HPC

HLRS is part of the Gauss Centre for Supercomputing (GCS), together with JSC in Jülich and LRZ in Garching near Munich. EuroCC@GCS is the German National Competence Centre (NCC) for High-Performance Computing. HLRS is also a member of the Baden-Württemberg initiative bwHPC.

This course is provided within the framework of the bwHPC training program.

Further courses

See the training overview and the Supercomputing Academy pages.