> Take a look at the safepoint profiler set-up analysis I did on this here: > "JVM detection of thread at safepoint" > > https://groups.google.com/d/msg/mechanical-sympathy/tepoA7PRFRU/-4-FjKbUBwAJ > Hi Alex.
If I understand this correctly it is grabbing the thread stack at the time it invokes the safepoint poll? I am quite new to using 'perf' so I did not manage to get your commands to work. $ sudo perf probe -d probe_libjvm:* "probe_libjvm:*" does not hit any event. Are you able to explain in more detail please ? (I am presumably missing something obvious) I think that the JDK 11 safepoint logging is already showing the PC when it reaches the safepoint (if I can trust it?) [2018-12-05T22:55:00.551+0000][safepoint] ... found polling page return exception at pc = 0x00007f3397c7deff, stub =0x00007f338fb4c900 from the perf-map generated for the Kafka process: 7f3397c7db40 80 Lkafka/server/ReplicaFetcherThread;::replicaId 7f3397c7dea0 80 Ljdk/internal/misc/Unsafe;::putIntUnaligned 7f3397c7e1c0 c0 Ljdk/internal/misc/Unsafe;::putIntUnaligned which puts the PC somewhere within Unsafe;::putIntUnaligned. ? Thanks, Ross -- You received this message because you are subscribed to the Google Groups "mechanical-sympathy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
