Tight bounds for parallel paging and green paging

In the parallel paging problem, there are p processors that share a cache of size k. The goal is to partition the cache among the processors over time in order to minimize their average completion time. For this long-standing open problem, we give tight upper and lower bounds of \u398(log p) on the competitive ratio with O(1) resource augmentation. A key idea in both our algorithms and lower bounds is to relate the problem of parallel paging to the seemingly unrelated problem of green paging. In green paging, there is an energy-optimized processor that can temporarily turn off one or more of its cache banks (thereby reducing power consumption), so that the cache size varies between a maximum size k and a minimum size k/p. The goal is to minimize the total energy consumed by the computation, which is proportional to the integral of the cache size over time. We show that any efficient solution to green paging can be converted into an efficient solution to parallel paging, and that any lower bound for green paging can be converted into a lower bound for parallel paging, in both cases in a black-box fashion. We then show that, with O(1) resource augmentation, the optimal competitive ratio for deterministic online green paging is \u398(log p), which, in turn, implies the same bounds for deterministic online parallel paging

The Network Architecture of the Connection Machine CM-5

The Connection Machine Model CM-5 Supercomputer is a massively parallel computer system designed to offer performance in the range of 1 teraflops (10 12 floating-point operations per second). The CM-5 obtains its high performance while offering ease of programming, flexibility, and reliability. The machine contains three communication networks: a data network, a control network, and a diagnostic network. This paper describes the organization of these three networks and how they contribute to the design goals of the CM-5. 1 Introduction In the design of a parallel computer, the engineering principle of economy of mechanism suggests that the machine should employ only a single communication network to convey information among the processors in the system. Indeed, many parallel computers contain only a single network: typically, a hypercube or a mesh. The Connection Machine Model CM-5 Supercomputer has three networks, however, and none is a hypercube or a mesh. This paper describes the..

The Network Architecture of the Connection Machine CM-5

The Connection Machine Model CM-5 Supercomputer is a massively parallel computer system designed to offer performance in the range of 1 teraflops (10 12 floating-point operations per second). The CM-5 obtains its high performance while offering ease of programming, flexibility, and reliability. The machine contains three communication networks: a data network, a control network, and a diagnostic network. This paper describes the organization of these three networks and how they contribute to the design goals of the CM-5. 1 Introduction In the design of a parallel computer, the engineering principle of economy of mechanism suggests that the machine should employ only a single communication network to convey information among the processors in the system. Indeed, many parallel computers contain only a single network: typically, a hypercube or a mesh. The Connection Machine Model CM-5 Supercomputer has three networks, however, and none is a hypercube or a mesh. This paper describes the..