Summary
The Grid technology is
transforming the form of carrying out computation, communication, interconnection
and the solution of large scale scientists problems, engineering and business.
Currently, there are numerous scientific and business projects that make use of Grid
technology with successful results. Such is the case of the LCG, The Large Hadron
Collider (LHC) Computing Grid, at CERN, the European organization for nuclear
research. It is the proliferation of independent Grids systems which has brought to
light the need for federal structures allowing integration and sustainable resource
control. The most representative example of this need it is the “European Grid
Initiative” (EGI). Although a Federated Grid can consist of several different types of
Grid infrastructures, is still based on the same principle that any Grid system, namely in
coordinating resources that are not subject to centralized control.
Scheduling problem is one of the best known in Computer Science,
however, applying existing scheduling
algorithms to a Federated Grid environment presents several problems, mainly for
scalability. So much so that with the emergence of such systems the trends in
scheduling have undergone a change of address from local to global scheduling. The
main reason why you can not take advantage of previous research is because the
assumptions that are the basis of centralized systems are not applicable in a Grid
environment. Therefore, scheduling strategies based on these ideas produce bad results
in practice. As a result, one of the most important objectives of this PhD is to
design a Federated Grid decentralized architecture based
on meta-schedulers.
Unlike the local manager, the meta-scheduler has an overview of the
entire Federated Grid. Therefore, fine-grain
scheduling policies are not appropriate for this level. These techniques are
better suited for local managers, since these completely control the resources found in
the layers closest to them. In contrast, the metascheduler needs light, decoupled, and
coarse-grain techniques. In this sense, the main objective of this PhD is
the study and analysis of various scheduling algorithms that follow these principles,
based on a performance model, enabling the scheduling of independent jobs in Federated
Grids and also able to reduce the makespan of applications and increase
performance of resources.
The main advantage of using a performance model on which to base our
mapping strategies lies in the lack of
dependence on resources state. In this respect, we find solutions, also at the
meta-scheduler level, who use information on the state of resources. However, it is
well known that centralized and hierarchical information services present significant
limitations, such as single point of failure, lack of scalability and high cost in
bandwidth.