SMiLE Shared
Memory Programming

Presenters:

Dr. Wolfgang Karl
http://wwwbode.in.tum.de/~karlw/
email: karlw@in.tum.de
Lehrstuhl für Rechnertechnik und Rechnerorganisation (LRR)
Institut für Informatik
Technische Universität München
D-80290 München
Germany
Tel: +49 89 289 28278
Fax: +49 89 289 28232

Martin Schulz
http://wwwbode.in.tum.de/~schulzm/
email: schulzm@in.tum.de
Lehrstuhl für Rechnertechnik und Rechnerorganisation (LRR)
Institut für Informatik
Technische Universität München
D-80290 München
Germany
Tel: +49 89 289 28399
Fax: +49 89 289 28232


For last few years the SMiLE (Shared Memory in a LAN-like Environment) project at LRR-TUM has investigated in the various aspects of SCI based clusters focusing on both hardware and software developments. As one result of these efforts, a comprehensive software infrastructure has been created and compiled supporting both message passing and shared memory style programming.

The latter one is based directly on the hardware DSM capabilities offered by SCI in order to fully exploit the performance potential of the network and is offered to the user at two different levels of abstraction: based on individually mapped segments of remote memory or using a transparent global virtual memory system. While the first is based on a straightforward implementation, the SISCI low-level API, but burdens the programmer with extra complexity, the second one provides a shared memory environment at a similar abstraction than SMPs, but requires a complex hybrid DSM system. Such a system, the SCI Virtual Memory or SCI-VM has been developed within SMiLE. Together with a general framework for arbitrary shared memory programming models, called HAMSTER (Hybrid-dsm based Modular and Adaptive Shared memory archiTEctuRe), it provides the means for an efficient and easy-to-use shared memory programming environment.

The presentation will introduce both models and describe their implementation, challenges, and applicability for the end user. It will discuss how they relate to each other and how they fit into the overall software infrastructure. This discussion will be based on many examples and will enable the participants to understand the issues involved in using SCI as the basis for shared memory programming.

 

 

SMiLE Shared
Memory Programming

 

During the lab, the participants will get a hands-on experience of shared memory programming on SCI. This part will be split into two parts: basic shared memory programming using the SISCI API and through a high-level programming model relying on the SCI Virtual Memory.