Testing for Non-Zero Values
Posted conditions have integer values assigned internally by a TIBCO Hawk agent. When a rulebase is loaded, values are set to 0 until the action is performed. Performing the action creates the posted condition and gives it a non-zero value, signifying that the condition does exist and has not yet been cleared. Although the value is internal, a test in another rule can check the posted condition for existence or non-zero values. Posted conditions that can be used in a test are listed along with other parameters in the Test Builder dialog.
For example, a rule could check CPU utilization every 60 seconds. If the CPU is greater than 80% utilized when the test is evaluated, a Post Condition action named SystemTooBusy
is performed and its integer value becomes non-zero. Another rule retrieving the process table every 60 seconds with a compound test to identify the processes consuming more that 50% of CPU when total usage exceeds 80% can be written as:
((%CPU>50) AND (SystemTooBusy>0))
If this test evaluates to true, an alert message that includes the PID for the process is generated. Results from multiple data sources are required to perform this monitoring task.