Grouse and Whistler Credit Union (G \& W) is a Vancouver-based credit union set up by a number of skiing clubs to service the financial needs of their members. The management of G \& W is aggressive, and they have invested heavily in computer systems as a means of providing their members with a vast and flexible range of services. They are especially proud of their HotDogger online system that allows members to use their own microcomputers to gain access to many of the services offered by the credit union.

In recent months, the membership of \(\mathrm{G} \& \mathrm{~W}\) has been increasing rapidly. Many of the new members are young, upwardly mobile professionals who have access to a microcomputer and who delight in using microcomputers in innovative ways. Accordingly, the demand for the services offered via the Hot-Dogger system has grown substantially.

With the growth in membership and increasing use of the Hot-Dogger system, response time for all online systems has declined. Management has been especially concerned that these slower response times will result in lost goodwill among the members. Consequently, managers have authorized the expansion of computer facilities to meet the increased demand for services.

To determine how the computer system should be expanded, an investigation of the existing facilities was carried out by the information systems manager at G \& W. On the basis of this investigation, she concluded that the primary reason for the declining response times was insufficient disk capacity. She argued that the Hot-Dogger system was now consuming considerable resources and that disk space was the bottleneck.

To rectify the situation, she recommended the purchase of five new disk drives and a disk controller to service the drives. She did not recommend the purchase of a new channel, however, as an investigation of channel utilization had shown that one of the channels in the system was only lightly utilized. The new controller and new disk drives were attached to this channel when they were installed.

The addition of the new controller and new disk drives produced no improvement in response times. In fact, response times continued to decline rapidly. Initially the information systems manager thought that the channel servicing the new controller and new disk drives might now be overloaded. Performance statistics indicated, however, that the channel was still only lightly utilized.

Required: You are an information systems auditor with expertise in computer performance evaluation. The information systems manager at G \& Whas asked you to examine her system and to advise her on the problems that exist and the remedial actions that will then be needed. Write a brief report advising her on

(a) the possible problems that could be causing the poor response times,

(b) the measurements you intend to take to isolate the problem, and

(c) the monitoring tools you will use to take the measurements.