.. |threshold| replace:: **-a/--auto**, **-i/--irq**, or **-T/--thread** .. |thresharg| replace:: -T .. |tracer| replace:: timerlat .. |actionsperf| replace:: For time-sensitive actions, it is recommended to run **rtla timerlat** with BPF support and RT priority. Note that due to implementational limitations, actions might be delayed up to one second after tracing is stopped if BPF mode is not available or disabled. **-a**, **--auto** *us* Set the automatic trace mode. This mode sets some commonly used options while debugging the system. It is equivalent to use **-T** *us* **-s** *us* **-t**. By default, *timerlat* tracer uses FIFO:95 for *timerlat* threads, thus equilavent to **-P** *f:95*. **-p**, **--period** *us* Set the *timerlat* tracer period in microseconds. **-i**, **--irq** *us* Stop trace if the *IRQ* latency is higher than the argument in us. **-T**, **--thread** *us* Stop trace if the *Thread* latency is higher than the argument in us. **-s**, **--stack** *us* Save the stack trace at the *IRQ* if a *Thread* latency is higher than the argument in us. **-t**, **--trace** \[*file*] Save the stopped trace to [*file|timerlat_trace.txt*]. **--dma-latency** *us* Set the /dev/cpu_dma_latency to *us*, aiming to bound exit from idle latencies. *cyclictest* sets this value to *0* by default, use **--dma-latency** *0* to have similar results. **--deepest-idle-state** *n* Disable idle states higher than *n* for cpus that are running timerlat threads to reduce exit from idle latencies. If *n* is -1, all idle states are disabled. On exit from timerlat, the idle state setting is restored to its original state before running timerlat. Requires rtla to be built with libcpupower. **-k**, **--kernel-threads** Use timerlat kernel-space threads, in contrast of **-u**. **-u**, **--user-threads** Set timerlat to run without a workload, and then dispatches user-space workloads to wait on the timerlat_fd. Once the workload is awakes, it goes to sleep again adding so the measurement for the kernel-to-user and user-to-kernel to the tracer output. **--user-threads** will be used unless the user specify **-k**. **-U**, **--user-load** Set timerlat to run without workload, waiting for the user to dispatch a per-cpu task that waits for a new period on the tracing/osnoise/per_cpu/cpu$ID/timerlat_fd. See linux/tools/rtla/sample/timerlat_load.py for an example of user-load code.