On Fri, Jun 30, 2017 at 6:12 AM, Nair, Reena via iovisor-dev <[email protected]> wrote: > Hi, > > > I am trying to track the scheduling events of a particular process using the > static tracepoint: sched_switch. > > A map entry is updated for each context switch, which is working fine, > however some of the events are missed while printing the value using > bpf_trace_printk() (Each context switch updates the value by '1', however > sometimes the output printed is not continuous). > > What could be the reason?
If you try to print too much in a very short period of time, kernel may skip some of prints. > > Why is it given that PERF_OUTPUT is better than bpf_trace_printk? perf_output is per process and bpf_trace_printk is global. > > Is there any way to use PERF_OUTPUT with static tracepoints? Yes. You can take a look at bcc/tests/python/test_usdt.py as an example. > > > Many Thanks, > > Reena > > > _______________________________________________ > iovisor-dev mailing list > [email protected] > https://lists.iovisor.org/mailman/listinfo/iovisor-dev > _______________________________________________ iovisor-dev mailing list [email protected] https://lists.iovisor.org/mailman/listinfo/iovisor-dev
