When Adaptive Server has no tasks to run, it loops (holds the CPU), looking for executable tasks. The configuration parameter runnable process search count controls the number of times that Adaptive Server loops.
With the default value of 2000, Adaptive Server loops 2000 times, looking for incoming client requests, completed disk I/Os, and new tasks in the run queue. If there is no activity for the duration of runnable process search count, Adaptive Server relinquishes the CPU to the operating - system.
The default for runnable process search count generally provides good response time, if the operating - system is not running clients other than Adaptive Server.
Use sp_sysmon to determine how runnable process search count affects Adaptive Server’s use of CPU cycles, engine yields to the operating - system, and blocking network checks.
See Performance and Tuning Guide: Tools for Monitoring and Analyzing Performance on using the sp_sysmon.