Browsing by Author "Simmonds, Robert William John"

Now showing 1 - 9 of 9
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    A generic execution management framework for long running jobs in grid environments
    (2012) Elahi, Tanvire; Simmonds, Robert William John; Unger, Brian W.
    Over the last decade, the grid has emerged as a paradigm of distributed and collaboraĀ­tive computing focusing on the sharing of computational and storage resources spanning across geographical and organizational domains. Greater access to high-end computaĀ­tional facilities provides researchers fom a broad spectrum of domains an inexpensive option of carrying out sophisticated computational experiments. However, the inherĀ­ent dynamics and heterogeneity of grid environments make the execution of resource and compute intensive applications a challenging task. Increasing fault tolerance by checkpointing and migrating jobs between resources requires significant expertise and intervention from users. Automation of such tasks can allow them to focus more on the scientific results and less on the technical details. This thesis addresses the issues associated with management of execution of long runĀ­ning applications in grid environments. It presents a generic framework for automating execution of such applications. The framework is driven by a set of information modĀ­els that capture knowledge about the resources and the applications. Crucial to the functioning of the framework is information on two application characteristics: the conĀ­figurability, and the memory usage behaviour. Separate models are presented to encode knowledge of both of these characteristics. Use of a common representation of knowledge abstracts the heterogeneity of both the resources and the applications and makes the framework functional without the need to be tailored to any specific application. Two important issues that need to be considered in managing job execution are the amount of memory required by the job and the wait time the job may experience on a specific resource. The framework presented in this thesis is equipped with mechanisms to address both of these issues. It is able to make estimations about the wait time for jobs with different resource requirements. A learning system has been designed as part of the framework to characterize the memory usage behaviour of application instances. The system facilitates execution management operations by providing accurate estimation of job's memory usage.
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    A gridFTP overlay network service
    (2006) Rizk, Philip; Unger, Brian W.; Simmonds, Robert William John
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    An SLA modelling language for utility computing
    (2009) Akshay, Abhinav; Simmonds, Robert William John
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    Coallocation of compute and storage resources in grid environments
    (2005) Gaurav, Abhishek; Simmonds, Robert William John
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    Grid computing with plan 9: an alternative solution for grid computing
    (2005) Mirtchovski, Andrey A.; Simmonds, Robert William John
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    Monitoring jobs in grid computing environments
    (2007) Adewale, Idowu Oluwafemi; Simmonds, Robert William John
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    Scheduling virtual machines in data centers
    (2009) Tan, Ting Xi; Simmonds, Robert William John
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    Supporting dynamic jobs in a grid environment
    (2009) Markatchev, Nayden; Simmonds, Robert William John
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    VO-centric account management
    (2007) Aikema, David; Simmonds, Robert William John
    Virtual organizations (VOs) are now being used by major grid computing projects such as LCG, associated with CERN's Large Hadron Collider, to reduce the cost and complexity of user management. Users may be able to gain access to resources at a service provider, based on attributes supplied by a virtual organization which has negotiated an access agreement with this service provider. A survey of existing virtual organization management and account management tools shows that these tools address access control through the passing of attributes in variĀ­ous forms. However, these tools provide only limited support for lifecycle management features such as the mapping of new users to accounts, management of renewals, and handling of account expiry. A model of account access control and lifecycle management is presented which capĀ­tures current system behaviours and sets a roadmap illustrating useful ways in which these tools may be extended.