-\li <b>MetaSimGrid : Towards realistic scheduling simulation of
- distributed applications</b>\n
- by <em>Arnaud Legrand and Julien Lerouge</em>\n
- Most scheduling problems are already hard on homogeneous
- platforms, they become quite intractable in an heterogeneous
- framework such as a metacomputing grid. In the best cases, a
- guaranteed heuristic can be found, but most of the time, it is
- not possible. Real experiments or simulations are often
- involved to test or to compare heuristics. However, on a
- distributed heterogeneous platform, such experiments are
- technically difficult to drive, because of the genuine
- instability of the platform. It is almost impossible to
- guarantee that a platform which is not dedicated to the
- experiment, will remain exactly the same between two tests,
- thereby forbidding any meaningful comparison. Simulations are
- then used to replace real experiments, so as to ensure the
- reproducibility of measured data. A key issue is the
- possibility to run the simulations against a realistic
- environment. The main idea of trace-based simulation is to
- record the platform parameters today, and to simulate the
- algorithms tomorrow, against the recorded data: even though it
- is not the current load of the platform, it is realistic,
- because it represents a fair summary of what happened
- previously. A good example of a trace-based simulation tool is
- SimGrid, a toolkit providing a set of core abstractions and
- functionalities that can be used to easily build simulators for
- specific application domains and/or computing environment
- topologies. Nevertheless, SimGrid lacks a number of convenient
- features to craft simulations of a distributed application
- where scheduling decisions are not taken by a single
- process. Furthermore, modeling a complex platform by hand is
- fastidious for a few hosts and is almost impossible for a real
- grid. This report is a survey on simulation for scheduling
- evaluation purposes and present MetaSimGrid, a simulator built
- on top of SimGrid.\n
- ftp://ftp.ens-lyon.fr/pub/LIP/Rapports/RR/RR2002/RR2002-28.ps.gz