Why is the "real time" so much greater than the "cpu time"

[govern at houxf.UUCP]

On my 4.1BSD system, the output of "time" for a long, CPU-intensive
program typically shows a "real time" about 20 times as high as the
CPU time, and the "user" time is often close to the real time.

1) Is this normal?  The ratio seems awfully high.  How can I check
to see if the system is running ok or if it needs tuning?

2) Exactly what times go into the CPU and user times?
	- When a process has  20% of the CPU, is the "CPU time"
		value scaled to reflect this?
	- Where does IO time fit in?
	- What about paging time? (The application was a very large
		simulation, so it has to page a lot.)

			Thanks;
			Bill Stewart
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