Cray XC40 Optimization, and Parallel I/O Courses

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Cray XC40 Optimization, and Parallel I/O Courses


In late August 2014 we entered the next step of our HPC systems installation phase: the new Cray XC40 super computer is installed. It delivers a peak performance of 4 Petaflops, outperforming the maximum performance of the previous system, Hermit, by a factor of about 4! This new HPC system provides 500 TB of Main Memory and about 6 PB of disc space. It is equipped with about 100,000 computing cores and features Intel’s next generation of micro processors, which are designed to optimize power savings and promise significant performance enhancements.

The three day optimization course covering the main topics of porting applications for the Cray XC40 system-Hornet, application profiling, application debugging, and parallel IO. Tools provided on the system are presented in talks and live demos. Furthermore a series of Hands-on sessions give the opportunity to exercise also with own applications.  

An increasing issue in parallel computing is the efficient handling of reading and writing files. The one day workshop "Efficient parallel IO" offers users the ability to gain insight on how to optimize the IO of an application. It shows methods and tools for parallel IO including MPI-IO, HDF5, NetCDF. Thus the time spend in reading and writing files can be significantly reduced, increasing the total efficiency of application.

The workshop does include some Cray specific information about tools but is still useful for IO on other systems as well.

General Information


CRAY XC40 Optimization Course

2015, Monday Mar. 02
9:30 – 10:00: Local registration
10.00 -17:30:  Computing and programming Environment CRAY XC40/ Hornet
- XC architecture, PE, modules, and libraries- Compiling and running applications including Hands-on sessions

2015, Tuesday Mar. 03
9:00 - 17:30: Performance analysis and optimization
- CrayPat, Reveal, Apprentice, Cray Profiler applied in Hands-on sessions

2015, Wednesday Mar. 04
9:00 - 17:30: Efficient Parallel Debugging
- ATP, STAT, lgdb, CCDB, Intel Inspector, Fast track debug and DDT, applied in Hands-on sessions

Efficient parallel IO

2015, Thursday Mar. 05
9:30 – 10:00: Local registration
10.00 -17:30 Efficient parallel IO 
-        Hardware overview, Lustre, Serial IO, IO Buffering, MPI-IO, HDF5, NetCDF




CRAY XC40 Optimization Course: Stefan Andersson, Aniello Esposito, Michael Neff and Mandes Schönherr (Cray)

Efficient parallel IO: Stefan Andersson


Academic participants (i.e., members of universities or public research institutions) from Europe or PRACE countries: Please apply through the PATC web page. After your registration, you will receive an automated "congratulation"-email about your successful registration. This email implies that you have a guaranteed seat in the course and you should organize your travel.

All other participants (not from academia, or from outside Europe), or if the PATC web page is temporarily unavailable, please apply through this online registration form

Series of two courses: Please book the appropriate days in the registration form!

Course number is 2015-XC40(1).


for registration is Feb. 19, 2015 (extended deadline).


Members of German universities and public research institutes: none.
Members of universities and public research institutes within Europe or PRACE: none.
Members of other universities and public research institutes: 120 EUR.  
Others: 400 EUR.
(includes food and drink at coffee breaks, will be collected on the first day of the course, cash only)

HLRS is part of the Gauss Centre for Supercomputing (GCS), which is one of the six PRACE Advanced Training Centres (PATCs) that started in Feb. 2012. The mandate for the PATCs is as follows: "The PRACE Advanced Training Centres will serve as European hubs of advanced, world-class training for researchers working in the computational sciences." (see D3.2.3)
This course is a PATC course, see also the PRACE Training Portal and Events. For participants from public research institutions in PRACE countries, the course fee is sponsored through the PRACE PATC program.

HLRS is also member of the Baden-Württemberg initiative bwHPC-C5.
This course is also provided within the framework of the bwHPC-C5 user Support.

Cancelation Policy

If you cannot come to the course, please send an email to the organizer as soon as possible. This would allow us to accept additional participants from the waiting-list. There is no cancelation fee.
NO-SHOW: Registered persons that do not cancel and do not show up without any reasons are blocked for the next year on any of our workshops (because it is too expensive to produce unused copies of the slides for them).


Each participant will get a paper copy of all slides.

Further courses

Shortcut-URL of this course:
and PATC web page:


Rolf Rabenseifner
phone 0711 685 65530

Joerg Hertzer
phone 0711 685 65932