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1**-a**, **--auto** *us*2 3 Set the automatic trace mode. This mode sets some commonly used options4 while debugging the system. It is equivalent to use **-T** *us* **-s** *us*5 **-t**. By default, *timerlat* tracer uses FIFO:95 for *timerlat* threads,6 thus equilavent to **-P** *f:95*.7 8**-p**, **--period** *us*9 10 Set the *timerlat* tracer period in microseconds.11 12**-i**, **--irq** *us*13 14 Stop trace if the *IRQ* latency is higher than the argument in us.15 16**-T**, **--thread** *us*17 18 Stop trace if the *Thread* latency is higher than the argument in us.19 20**-s**, **--stack** *us*21 22 Save the stack trace at the *IRQ* if a *Thread* latency is higher than the23 argument in us.24 25**-t**, **--trace** \[*file*]26 27 Save the stopped trace to [*file|timerlat_trace.txt*].28 29**--dma-latency** *us*30 Set the /dev/cpu_dma_latency to *us*, aiming to bound exit from idle latencies.31 *cyclictest* sets this value to *0* by default, use **--dma-latency** *0* to have32 similar results.33 34**-k**, **--kernel-threads**35 36 Use timerlat kernel-space threads, in contrast of **-u**.37 38**-u**, **--user-threads**39 40 Set timerlat to run without a workload, and then dispatches user-space workloads41 to wait on the timerlat_fd. Once the workload is awakes, it goes to sleep again42 adding so the measurement for the kernel-to-user and user-to-kernel to the tracer43 output. **--user-threads** will be used unless the user specify **-k**.44 45**-U**, **--user-load**46 47 Set timerlat to run without workload, waiting for the user to dispatch a per-cpu48 task that waits for a new period on the tracing/osnoise/per_cpu/cpu$ID/timerlat_fd.49 See linux/tools/rtla/sample/timerlat_load.py for an example of user-load code.50