#!/usr/bin/env bpftrace

BEGIN
{
    printf("Tracing Julia GC Times... Hit Ctrl-C to end.\n");
}

usdt:usr/lib/libjulia-internal.so:julia:gc__begin
{
    $now = nsecs;
    @time[pid] = $now;
    @start[pid] = $now;
}

usdt:usr/lib/libjulia-internal.so:julia:gc__stop_the_world
/@start[pid]/
{
    $now = nsecs;
    @stop_the_world_usecs[pid] = hist(($now - @time[pid]) / 1000);
    @time[pid] = $now;
}

usdt:usr/lib/libjulia-internal.so:julia:gc__end
/@start[pid]/
{
    $now = nsecs;
    @gc_total_usecs[pid] = hist(($now - @start[pid]) / 1000);
    @gc_phase_usecs[pid] = hist(($now - @time[pid]) / 1000);
    @time[pid] = $now;
    delete(@start[pid]);
}

usdt:usr/lib/libjulia-internal.so:julia:gc__finalizer
/@time[pid]/
{
    @finalizer[pid] = hist((nsecs - @time[pid]) / 1000);
    delete(@time[pid]);
}

END
{
    clear(@start);
    clear(@time);
}