The Experts below are selected from a list of 84963 Experts worldwide ranked by ideXlab platform
Mendel Rosenblum - One of the best experts on this subject based on the ideXlab platform.
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disco running commodity operating systems on scalable Multiprocessors
ACM Transactions on Computer Systems, 1997Co-Authors: Edouard Bugnion, Scott W Devine, Kinshuk Govil, Mendel RosenblumAbstract:In this article we examine the problem of extending modern operating systems to run efficiently on large-scale shared-memory Multiprocessors without a large implementation effort. Our approach brings back an idea popular in the 1970s: virtual machine monitors. We use virtual machines to run multiple commodity operating systems on a scalable multiprocessor. This solution addresses many of the challenges facing the system software for these machines. We demonstrate our approach with a prototype called Disco that runs multiple copies of Silicon Graphics' IRIX operating system on a multiprocessor. Our experience shows that the overheads of the monitor are small and that the approach provides scalability as well as the ability to deal with the nonuniform memory access time of these systems. To reduce the memory overheads associated with running multiple operating systems, virtual machines transparently share major data structures such as the program code and the file system buffer cache. We use the distributed-system support of modern operating systems to export a partial single system image to the users. The overall solution achieves most of the benefits of operating systems customized for scalable Multiprocessors, yet it can be achieved with a significantly smaller implementation effort.
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disco running commodity operating systems on scalable Multiprocessors
Symposium on Operating Systems Principles, 1997Co-Authors: Edouard Bugnion, Scott W Devine, Mendel RosenblumAbstract:In this paper we examine the problem of extending modern operating systems to run efficiently on large-scale shared memory Multiprocessors without a large implementation effort. Our approach brings back an idea popular in the 1970s, virtual machine monitors. We use virtual machines to run multiple commodity operating systems on a scalable multiprocessor. This solution addresses many of the challenges facing the system software for these machines. We demonstrate our approach with a prototype called Disco that can run multiple copies of Silicon Graphics' IRIX operating system on a multiprocessor. Our experience shows that the overheads of the monitor are small and that the approach provides scalability as well as the ability to deal with the non-uniform memory access time of these systems. To reduce the memory overheads associated with running multiple operating systems, we have developed techniques where the virtual machines transparently share major data structures such as the program code and the file system buffer cache. We use the distributed system support of modern operating systems to export a partial single system image to the users. The overall solution achieves most of the benefits of operating systems customized for scalable Multiprocessors yet it can be achieved with a significantly smaller implementation effort.
Sanjoy Baruah - One of the best experts on this subject based on the ideXlab platform.
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on line scheduling on uniform Multiprocessors
Real-Time Systems Symposium, 2001Co-Authors: Shelby Funk, Joël Goossens, Sanjoy BaruahAbstract:Each processor in a uniform multiprocessor machine is characterized by a speed or computing capacity, with the interpretation that a job executing on a processor with speed s for t time units completes (s/spl times/t) units of execution. The on-line scheduling of hard-real-time systems, in which all jobs must complete by specified deadlines, on uniform multiprocessor machines is considered It is known that online algorithms tend to perform very poorly in scheduling such hard-real-time systems on Multiprocessors; resource-augmentation techniques are presented here that permit online algorithms to perform better than may be expected given the inherent limitations. Results derived here are applied to the scheduling of periodic task systems on uniform multiprocessor machines.
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ECRTS - Task assignment on uniform heterogeneous Multiprocessors
17th Euromicro Conference on Real-Time Systems (ECRTS'05), 1Co-Authors: Shelby Funk, Sanjoy BaruahAbstract:The partitioning of periodic task systems upon uniform Multiprocessors is considered. In the partitioned approach to scheduling periodic tasks upon Multiprocessors, each task is assigned to a specific processor and all jobs generated by a task are required to execute upon the processor to which the task is assigned. A uniform heterogeneous multiprocessor is a multiprocessor in which each processor has an associated speed - a processor of speed s operating for t units of time will perform s /spl times/ t units of work. Partitioning of periodic task systems requires solving the bin-packing problem, which is known to be intractable (NP-hard in the strong sense). This paper presents methods for finding an approximate utilization bound for partitioned scheduling on uniform heterogeneous Multiprocessors.
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ECRTS - Characteristics of EDF schedulability on uniform Multiprocessors
15th Euromicro Conference on Real-Time Systems 2003. Proceedings., 1Co-Authors: Shelby Funk, Sanjoy BaruahAbstract:In uniform multiprocessor platforms, the various processors comprising the multiprocessor platform may have different computing capacities. The focus of this paper is the design of efficient tests for determining whether the earliest deadline first scheduling algorithm (EDF) can successfully schedule a given real-time task system to meet all deadlines upon a specified uniform multiprocessor platform. Upon uniform multiprocessor platforms, we show that it is often far easier (from a computational complexity perspective) to determine feasibility than it is to check for EDF-schedulability. In designing an EDF-schedulability test for uniform Multiprocessors, therefore, our approach is as follows: for a given uniform multiprocessor platform, we attempt to efficiently identify all those uniform multiprocessor platforms such that any real-time instance feasible upon these platforms is guaranteed to be EDF-schedulable upon the platform under consideration. EDF-schedulability upon the given platform can then be determined by ascertaining whether the real-time system is feasible upon any of these platforms.
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RTSS - On-line scheduling on uniform Multiprocessors
Proceedings 22nd IEEE Real-Time Systems Symposium (RTSS 2001) (Cat. No.01PR1420), 1Co-Authors: Shelby Funk, Joël Goossens, Sanjoy BaruahAbstract:Each processor in a uniform multiprocessor machine is characterized by a speed or computing capacity, with the interpretation that a job executing on a processor with speed s for t time units completes (s/spl times/t) units of execution. The on-line scheduling of hard-real-time systems, in which all jobs must complete by specified deadlines, on uniform multiprocessor machines is considered It is known that online algorithms tend to perform very poorly in scheduling such hard-real-time systems on Multiprocessors; resource-augmentation techniques are presented here that permit online algorithms to perform better than may be expected given the inherent limitations. Results derived here are applied to the scheduling of periodic task systems on uniform multiprocessor machines.
Edouard Bugnion - One of the best experts on this subject based on the ideXlab platform.
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disco running commodity operating systems on scalable Multiprocessors
ACM Transactions on Computer Systems, 1997Co-Authors: Edouard Bugnion, Scott W Devine, Kinshuk Govil, Mendel RosenblumAbstract:In this article we examine the problem of extending modern operating systems to run efficiently on large-scale shared-memory Multiprocessors without a large implementation effort. Our approach brings back an idea popular in the 1970s: virtual machine monitors. We use virtual machines to run multiple commodity operating systems on a scalable multiprocessor. This solution addresses many of the challenges facing the system software for these machines. We demonstrate our approach with a prototype called Disco that runs multiple copies of Silicon Graphics' IRIX operating system on a multiprocessor. Our experience shows that the overheads of the monitor are small and that the approach provides scalability as well as the ability to deal with the nonuniform memory access time of these systems. To reduce the memory overheads associated with running multiple operating systems, virtual machines transparently share major data structures such as the program code and the file system buffer cache. We use the distributed-system support of modern operating systems to export a partial single system image to the users. The overall solution achieves most of the benefits of operating systems customized for scalable Multiprocessors, yet it can be achieved with a significantly smaller implementation effort.
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disco running commodity operating systems on scalable Multiprocessors
Symposium on Operating Systems Principles, 1997Co-Authors: Edouard Bugnion, Scott W Devine, Mendel RosenblumAbstract:In this paper we examine the problem of extending modern operating systems to run efficiently on large-scale shared memory Multiprocessors without a large implementation effort. Our approach brings back an idea popular in the 1970s, virtual machine monitors. We use virtual machines to run multiple commodity operating systems on a scalable multiprocessor. This solution addresses many of the challenges facing the system software for these machines. We demonstrate our approach with a prototype called Disco that can run multiple copies of Silicon Graphics' IRIX operating system on a multiprocessor. Our experience shows that the overheads of the monitor are small and that the approach provides scalability as well as the ability to deal with the non-uniform memory access time of these systems. To reduce the memory overheads associated with running multiple operating systems, we have developed techniques where the virtual machines transparently share major data structures such as the program code and the file system buffer cache. We use the distributed system support of modern operating systems to export a partial single system image to the users. The overall solution achieves most of the benefits of operating systems customized for scalable Multiprocessors yet it can be achieved with a significantly smaller implementation effort.
Shelby Funk - One of the best experts on this subject based on the ideXlab platform.
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on line scheduling on uniform Multiprocessors
Real-Time Systems Symposium, 2001Co-Authors: Shelby Funk, Joël Goossens, Sanjoy BaruahAbstract:Each processor in a uniform multiprocessor machine is characterized by a speed or computing capacity, with the interpretation that a job executing on a processor with speed s for t time units completes (s/spl times/t) units of execution. The on-line scheduling of hard-real-time systems, in which all jobs must complete by specified deadlines, on uniform multiprocessor machines is considered It is known that online algorithms tend to perform very poorly in scheduling such hard-real-time systems on Multiprocessors; resource-augmentation techniques are presented here that permit online algorithms to perform better than may be expected given the inherent limitations. Results derived here are applied to the scheduling of periodic task systems on uniform multiprocessor machines.
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ECRTS - Task assignment on uniform heterogeneous Multiprocessors
17th Euromicro Conference on Real-Time Systems (ECRTS'05), 1Co-Authors: Shelby Funk, Sanjoy BaruahAbstract:The partitioning of periodic task systems upon uniform Multiprocessors is considered. In the partitioned approach to scheduling periodic tasks upon Multiprocessors, each task is assigned to a specific processor and all jobs generated by a task are required to execute upon the processor to which the task is assigned. A uniform heterogeneous multiprocessor is a multiprocessor in which each processor has an associated speed - a processor of speed s operating for t units of time will perform s /spl times/ t units of work. Partitioning of periodic task systems requires solving the bin-packing problem, which is known to be intractable (NP-hard in the strong sense). This paper presents methods for finding an approximate utilization bound for partitioned scheduling on uniform heterogeneous Multiprocessors.
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ECRTS - Characteristics of EDF schedulability on uniform Multiprocessors
15th Euromicro Conference on Real-Time Systems 2003. Proceedings., 1Co-Authors: Shelby Funk, Sanjoy BaruahAbstract:In uniform multiprocessor platforms, the various processors comprising the multiprocessor platform may have different computing capacities. The focus of this paper is the design of efficient tests for determining whether the earliest deadline first scheduling algorithm (EDF) can successfully schedule a given real-time task system to meet all deadlines upon a specified uniform multiprocessor platform. Upon uniform multiprocessor platforms, we show that it is often far easier (from a computational complexity perspective) to determine feasibility than it is to check for EDF-schedulability. In designing an EDF-schedulability test for uniform Multiprocessors, therefore, our approach is as follows: for a given uniform multiprocessor platform, we attempt to efficiently identify all those uniform multiprocessor platforms such that any real-time instance feasible upon these platforms is guaranteed to be EDF-schedulable upon the platform under consideration. EDF-schedulability upon the given platform can then be determined by ascertaining whether the real-time system is feasible upon any of these platforms.
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RTSS - On-line scheduling on uniform Multiprocessors
Proceedings 22nd IEEE Real-Time Systems Symposium (RTSS 2001) (Cat. No.01PR1420), 1Co-Authors: Shelby Funk, Joël Goossens, Sanjoy BaruahAbstract:Each processor in a uniform multiprocessor machine is characterized by a speed or computing capacity, with the interpretation that a job executing on a processor with speed s for t time units completes (s/spl times/t) units of execution. The on-line scheduling of hard-real-time systems, in which all jobs must complete by specified deadlines, on uniform multiprocessor machines is considered It is known that online algorithms tend to perform very poorly in scheduling such hard-real-time systems on Multiprocessors; resource-augmentation techniques are presented here that permit online algorithms to perform better than may be expected given the inherent limitations. Results derived here are applied to the scheduling of periodic task systems on uniform multiprocessor machines.
Joël Goossens - One of the best experts on this subject based on the ideXlab platform.
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Predictability of Fixed-Job Priority Schedulers on Heterogeneous Multiprocessor Real-Time Systems
Information Processing Letters, 2010Co-Authors: Liliana Cucu-grosjean, Joël GoossensAbstract:The multiprocessor Fixed-Job Priority (FJP) scheduling of real-time systems is studied. An important property for the schedulability analysis, the predictability (regardless to the execution times), is studied for heterogeneous multiprocessor platforms. Our main contribution is to show that any FJP schedulers are predictable on unrelated platforms. A convenient consequence is the fact that any FJP schedulers are predictable on uniform Multiprocessors.
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on line scheduling on uniform Multiprocessors
Real-Time Systems Symposium, 2001Co-Authors: Shelby Funk, Joël Goossens, Sanjoy BaruahAbstract:Each processor in a uniform multiprocessor machine is characterized by a speed or computing capacity, with the interpretation that a job executing on a processor with speed s for t time units completes (s/spl times/t) units of execution. The on-line scheduling of hard-real-time systems, in which all jobs must complete by specified deadlines, on uniform multiprocessor machines is considered It is known that online algorithms tend to perform very poorly in scheduling such hard-real-time systems on Multiprocessors; resource-augmentation techniques are presented here that permit online algorithms to perform better than may be expected given the inherent limitations. Results derived here are applied to the scheduling of periodic task systems on uniform multiprocessor machines.
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RTSS - On-line scheduling on uniform Multiprocessors
Proceedings 22nd IEEE Real-Time Systems Symposium (RTSS 2001) (Cat. No.01PR1420), 1Co-Authors: Shelby Funk, Joël Goossens, Sanjoy BaruahAbstract:Each processor in a uniform multiprocessor machine is characterized by a speed or computing capacity, with the interpretation that a job executing on a processor with speed s for t time units completes (s/spl times/t) units of execution. The on-line scheduling of hard-real-time systems, in which all jobs must complete by specified deadlines, on uniform multiprocessor machines is considered It is known that online algorithms tend to perform very poorly in scheduling such hard-real-time systems on Multiprocessors; resource-augmentation techniques are presented here that permit online algorithms to perform better than may be expected given the inherent limitations. Results derived here are applied to the scheduling of periodic task systems on uniform multiprocessor machines.
