My Oracle "imp" processes sleep quite frequently

[Ravi S. Banda]

I kicked off about 10+ oracle "imp" processes in parallel. Each import process imports one HUGE table at a time. There are no dependencies among them.
I understand processes go to sleep and are swapped out from the run-queue when they are waiting for resources. I also understand that no CPU usage is consumed when out of the run-queue and sleeping.
But, what is the problem?
Sar -Mu 5 5 shows:
14:35:54 cpu %usr %sys %wio %idle
Average 0 34 11 15 40
Average 1 31 12 11 45
Average 2 33 12 9 46
Average 3 32 12 9 47
Average 4 34 12 10 45
Average 5 33 13 10 44
Average 6 36 11 9 45
Average 7 39 12 6 43
Average system 34 12 10 44

sar -d 5 5 shows:
14:37:28 device %busy avque r+w/s blks/s avwait avserv
Average c0t6d0 0.64 0.50 1 18 0.00 7.05
Average c20t0d0 77.11 0.55 721 22052 0.01 1.51

Obviously, c20t0d0 (SAN disk) is showing the maximum activity. But the SAN disk has been created as a LUN from a disk pool / group of multiple disks physically on the EVA5000 disk array. I don't understand. Please help!

[Zdenek Spacek]

That's absolutely normal

No CPU cycles are burnt when waiting for I/O to complete. Since you are importing large tables, most of the time your process waits (in sleep mode) for your san to finish reading or writing.

[Sandman!]

Even though it most likely is disk I/O but it would help in narrowing down the source of sleeps and waits with the use of glance.

[Bill Hassell]

There's nothing to fix. The programs are doing what they were designed to do. What were you expecting?

[Ravi S. Banda]

Thank you, all. points will be assigned.
-- Ravi.