Re: [lttng-dev] Profiling LTTng tracepoint latency on different arm platforms
Mathieu Desnoyers via lttng-dev <[email protected]>
| Newsgroups | org.lttng.lists.lttng-dev |
|---|---|
| Message-ID | <[email protected]> |
On 6/20/23 10:20, Mathieu Desnoyers via lttng-dev wrote: > On 6/20/23 06:27, Mousa, Anas via lttng-dev wrote: >> Hello, > >> >> Arethereanysuggestionstorootcausethehighlatencyandpotentiallyimproveiton*platform****1*? >> >> Thanks and best regards, >> >> Anas. >> > > I recommend using "perf" when tracing with the sample program in a loop > to figure out the hot spots. With that information on the "fast" and > "slow" system, we might be able to figure out what differs. > > Also, comparing the kernel configurations of the two systems can help. > Also comparing the glibc versions of the two systems would be relevant. > Also make sure you benchmark the lttng "snapshot" mode [1] to make sure you don't run into a situation where the disk/network I/O throughput cannot cope with the generated event throughput, thus causing the ring buffer to discard events. This would therefore "speed up" tracing from the application perspective because discarding an event is faster than writing it to a ring buffer. Thanks, Mathieu [1] https://lttng.org/docs/v2.13/#doc-taking-a-snapshot > Thanks, > > Mathieu > > -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com _______________________________________________ lttng-dev mailing list [email protected] https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev