Search

link to homepage

Institute for Advanced Simulation (IAS)

Navigation and service



LinkTest: Parallel MPI PingPong Test

-> version 1.2p1 now available (see Release notes)

The Linktest program is a parallel ping-pong test between all possible MPI connections of a machine. Output of this program is a full communication matrix which shows the bandwidth and message latency between each processor pair and a report including the minimum bandwidth. The linktest runs for n processors in n steps where in each step n/2 pairs of processors will perform the MPI pingpong test (e.g. 3 iterations, 128 kB messages). The selection of the pairs is random but after running all steps all possible pairs are covered.

Linktest Output (Matrix) Linktest Output (Histogram)
Sample output of Linktest consisting of communication matrix and histogram

LinkTest is designed and optimized to run on very large numbers of MPI tasks (tested on 1.8 million tasks on JUQUEEN, Blue Gene/Q). Therefore also I/O (e.g. writing communication matrix) is implemented in parallel, using the parallel I/O library SIONlib.

Further informations:
-> Using LinkTest
-> Release Notes
-> Copyright
-> Download and Installation

Contact: linktest.jsc@fzj-juelich.de
WWW: http://www.fz-juelich.de/jsc/linktest


Servicemeu

Logo

 

 

 

YOUR OPINION MATTERS!

 

Dear visitor,

To make our website suit your needs even more and to give it a more appealing design, we would like you to answer a few short questions.

Answering these questions will take approx. 10 min.

Start now Close window

Thank you for your support!

 

In case you have already taken part in our survey or in case you have no time to take part now, you can simply close the window by clicking "close".

If you have any questions on the survey, please do not hesitate to contact: webumfrage@fz-juelich.de.

 

Your Team at Forschungszentrum Jülich

 

Note: Forschungszentrum Jülich works with the market research institute SKOPOS to anonymously conduct and analyze the survey. SKOPOS complies with the statutory requirements on data protection as well as with the regulations of ADM (Arbeitskreis Deutscher Markt- und Sozialforschungsinstitute e.V.) and ESOMAR (Europäische Gesellschaft für Meinungs- und Marketingforschung). Your data will not be forwarded to third parties.