Xiao Liu PhD Thesis.pdf - Faculty of Information and Communication ...

which can be further investigated in the future:
1) Forecasting strategy: our forecasting strategy focuses on data/computation
intensive activities. In the future, we will investigate the adaptation of our
forecasting strategy for other types of cloud workflow activities such as instance
intensive activities in business cloud workflow applications.
2) Setting strategy: our setting strategy can achieve a set of high quality coarsegrained
and fine-grained temporal constraints at build time. In the future, we will
investigate the updating strategy for temporal constraints at runtime to
accommodate significant changes such as new user requirements and QoS
contract changes.
3) Checkpoint selection and temporal verification: with the novel probability based
temporal consistency model, our strategy can significantly reduce the times for
checkpoint selection and temporal verification. In the future, the time-series
patterns for different types of temporal violations will be investigated to further
improve the efficiency of checkpoint selection and temporal verification.
4) Temporal violation handling point selection: the experimental results have
shown that our adaptive temporal violation handling strategy can achieve
satisfactory performance in most simulated system environments. In the future,
we will test our strategy with more real world workflow applications.
5) Light-weight temporal violation handling strategies: more metaheuristics
algorithms will be investigated and compared with our general two-stage
workflow local rescheduling strategy. Meanwhile, some other light-weight
strategies may also be investigated to supplement standalone rescheduling
strategies, especially to overcome the scenarios when the work loads of current
resources are very high.
6) Non-recoverable temporal violations: This thesis has focused on statistically
recoverable temporal violations. Although the probability of non-recoverable
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