dunc@eecg.toronto.edu (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.