Why should disk queue length above zero be used to identify bottlenecks?
A.
This indicates excessive I/O and a disk bottleneck.
B.
This indicates excessive swap file utilization.
C.
This indicates insufficient RAM.
D.
This indicates a failed disk.
Explanation:
http://www.ithacks.com/2008/09/12/high-avg-disk-queue-length-and-finding-the-cause/