email@example.com (Duncan Elliott) (01/13/90)
Electrical Engineering Computer Group Cider Seminar Series A Load Balancing Facility for Distributed Systems by Pierre Delisle Computer Science University of Toronto Time: Friday, Jan. 19, 1990, 12:05 --- Place: GB 220 The advent of distributed systems has created new challenges in the area of resource sharing. While the sharing of data and peripherals is a fairly common occurrence, intelligent sharing of processing resources is not. Yet, experience has shown that at a given instant in time, some nodes sit virtually idle while others are heavily loaded. Also, the heterogeneity often found in the hardware configuration of distributed systems presents the opportunity for more effective sharing of the system workload. For these reasons, transparent and efficient access to the processing resources of other machines has become increasingly desirable in order to improve overall system performance. In this talk, we present the design, implementation and evaluation under live workloads of a general purpose load balancing facility for loosely-coupled distributed systems. The load balancing facility works at the shell level, and requires no modification to the operating system or application software. The load balancing algorithm employs a multi-class eligibility scheme (where resource requirements of eligible jobs may be specified) and a multi-resource information scheme (where multiple load indices are used to represent contention at each node) to improve placement decisions. The flexibility of the implementation makes it relatively easy to take into account the heterogeneity of the network, and to adapt it to a wide variety of distributed environments. Performance data obtained under live workloads clearly indicate that dynamic load balancing at the job level can be easily implemented as a system facility in loosely-coupled distributed systems, and that it has the potential to substantially improve overall system performance.