The tick-n probes fire at fixed intervals, at a high interrupt level on only one CPU per interval. Unlike profile-n probes, which fire on every CPU, tick-n probes fire on only one CPU per interval and the CPU on which they fire can change over time. The units of n default to a frequency expressed as a rate of firing per second, but the value can also have an optional time suffix as shown in Table 11.1, “Valid Time Suffixes”, which specifies either a time interval or a frequency.

The tick-n probes have several uses, such as providing some periodic output or taking a periodic action.