The -d option, of the sar command, does not appear to have been implemented in A/UX 3.1.x on the AWS 95. Although the -d option did not generate any error messages, it returned nothing. For example, "sar -d 1 10" returned the time stamp every second 10 times.
You can try to use the -b and/or the -w option to monitor the block device buffering and swapping activities. For example,
sar -b 1 1000
sar -w 1 1000
These two options are close to monitoring the disk activity you are looking for. For tuned performance, the system reports should be 100% of buffer caches and 0% for swapping activity.
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