15-17 June 2021
ONLINE COURSE
Europe/Vienna timezone

Dr. Claudia Blaas-Schenner

This course will be delivered as an ONLINE COURSE (using Zoom) for remote participation.

REGISTRATION is strictly NECESSARY since the details to access the online course will be provided to the registered and accepted attendees only. Registration follows the "first come – first served" principle. For the online course we can take a maximum of 40 persons. Additional registrations will be added to a waiting list.

Furthermore, accepted participants will be contacted a few days before the course and asked to do a short PRE-ASSIGNMENT that has to be completed before the course starts.

The HANDS-ON LABS will be done on the Austrian flagship supercomputer VSC-4, all participants will get a training user account at VSC-4 for the duration of the course.

Overview

Most HPC systems are clusters of shared memory nodes. To use such systems efficiently both memory consumption and communication time has to be optimized. Therefore, hybrid programming may combine the distributed memory parallelization on the node interconnect (e.g., with MPI) with the shared memory parallelization inside of each node (e.g., with OpenMP or MPI-3.0 shared memory). This course analyzes the strengths and weaknesses of several parallel programming models on clusters of SMP nodes. Multi-socket-multi-core systems in highly parallel environments are given special consideration. MPI-3.0 has introduced a new shared memory programming interface, which can be combined with inter-node MPI communication. It can be used for direct neighbor accesses similar to OpenMP or for direct halo copies, and enables new hybrid programming models. These models are compared with various hybrid MPI+OpenMP approaches and pure MPI. Numerous case studies and micro-benchmarks demonstrate the performance-related aspects of hybrid programming.

Hands-on sessions are included on all days. Tools for hybrid programming such as thread/process placement support and performance analysis are presented in a "how-to" section. This course provides scientific training in Computational Science and, in addition, the scientific exchange of the participants among themselves.

Content Levels: Beginners = 0:00h (0%) + Intermediate = 1:30h (10%) + Advanced = 13:30h (90%)

This course is a PRACE training event. It is organized by the VSC Research Center, TU Wien, in cooperation with HLRS and RRZE.

Agenda & Content

1st day – 15 June 2021

08:45   Join online
09:00      Welcome
09:05      Motivation
09:15      Introduction
09:30      Programming Models
09:35         - MPI + OpenMP
10:00            Practical (how to compile and start)
10:30   Break
10:45         - continue: MPI + OpenMP
11:30   Break
11:45         - continue: MPI + OpenMP
12:30            Practical (how to do pinning)
13:00   Lunch
14:00            Practical (hybrid through OpenMP parallelization)
15:30            Q & A, Discussion
16:00   End of first day

2nd day – 16 June 2021

08:45   Join online
09:00         - Overlapping Communication and Computation
09:30            Practical (taskloops)
10:30   Break
10:45         - MPI + OpenMP Conclusions
11:00         - MPI + Accelerators
11:30      Tools
11:45   Break
12:00      Programming Models (continued)
12:05         - MPI + MPI-3.0 Shared Memory
13:00   Lunch
14:00            Practical (replicated data)
15:30            Q & A, Discussion
16:00   End of second day

3rd day – 17 June 2021

08:45   Join online
09:00         - MPI Memory Models and Synchronization
09:40         - Pure MPI
10:00   Break
10:15         - Recap - MPI Virtual Topologies
10:45         - Topology Optimization
11:15   Break
11:30           Practical/Demo (application aware Cartesian topology)
12:30         - Topology Optimization (Wrap up)
12:45       Conclusions
13:00   Lunch
14:00       Finish the hands-on labs, Discussion, Q & A, Feedback
16:00   End of third day (course)

Starts
Ends
Europe/Vienna
ONLINE COURSE
VSC Research Center, TU Wien

Prerequisites:

Basic MPI and OpenMP knowledge as presented in the VSC courses on MPI and OpenMP.
For the hands-on sessions you should know Unix/Linux and either C/C++ or Fortran.
Hands-on labs: The hands-on labs will be done on the Austrian flagship supercomputer VSC-4, all participants will get a training user account at VSC-4 for the duration of the course.
Language: English

Teachers:

Dr. habil. Georg Hager (RRZE, Uni. Erlangen), Dr. Rolf Rabenseifner (HLRS, Uni. Stuttgart), Dr. Claudia Blaas-Schenner (VSC Research Center, TU Wien), David Fischak (tutor; VSC Research Center, TU Wien)
Registration: Registration form – Registration period is from 12 April 2021 to 6 June 2021, and follows the "first come – first served" principle. For the online course we can take a maximum of 40 persons. Additional registrations will be added to a waiting list.
Fees: This course is a PRACE Training Center (PTC) event. Therefore, the course is free of charge for all participants from the EU or from PRACE-member-countries.
Further webpages: This course is also announced by the VSC Research Center, TU Wien.

 

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