Reference Guide

Rules 151
DiskIO Rules
DiskIO Rules
Rules in this section:
• Volume_Busy
Volume_Busy
Purpose
This rule detects volumes that cause performance bottlenecks. Bottlenecks occur when a
disk is highly utilized and performs a high rate of read and write transactions.
Note Volume bottlenecks are the largest contributor to performance degradation. Investigate all
critical warnings immediately.
Scope
DiskIO_Volumes
Rule Definition
Condition State
Disk volume utilization exceeds 30% AND the service time exceeds
50 milliseconds
Critical
Disk volume utilization exceeds 20% AND the service time exceeds
30 milliseconds
Warning
Disk volume utilization is less than 20% AND the service time
exceeds 30 milliseconds
Normal