Recent trends in grid scheduling system research represent a
movement from centralized based scheduling models to decentralize and
hierarchical model due to the lack of dependability and low resource
efficiency. Hierarchical models have special notice for some researches,
whereas some others believe that it is a type of the centralized model
and its disadvantages can also be generalized in the hierarchical model.
besides, it can get both advantages of the decentralized and centralized
model if we improve some scheduling components in resource management
section. One of these components in the hierarchical scheduling
system is the resource discovery and updating management. The
basic reason that we cannot take advantage of earlier research is
the assumptions that underlying centralized and hierarchical
models do not hold in grid circumstances and feasibly make weak grid
schedules. In this research, our proposed method is considered as
a combinational scheduling model based on hierarchical and
decentralized models. We have utilized advantages of a
decentralized model between local schedulers in which each local
scheduler can schedule a job independently based on found
available nodes if there have been sufficient member nodes in its
own sites (or branches). However, if it could not schedule a job,
it devolve job to up-level schedulers. In this model,
meta-scheduler, as the high-level scheduler, is the root of
scheduling system such as other hierarchical architectures, but it
has less intervention in this model. Obvious that this paper does
not concentrate on scheduling methods or models, but it argues
about the procedures of available nodes detection and using
obtained information on the basis of hierarchical architecture. In
practice, our proposed mechanism is separated into two components.
The first component is responsible for online detecting available
nodes and updating their status. The second component is to
identify sufficiently required nodes for the requester (job owner
or consumer) based on input parameters (job status).
Edited
version of the preceding passage
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