gevent_tracer.py

gevent_tracer.py

def _callback(event, args):

    # switch and throw both switch the active greenlet from origin to target
    if event not in set(['switch', 'throw']):
        return

    origin, target = args

    # record last switch (time and CPU tick)
    global __last_switch_time_ms, __last_switch_cpu_tick
    then_time, then_tick = __last_switch_time_ms, __last_switch_cpu_tick
    now_time, now_tick = switch_timer()
    __last_switch_time_ms, __last_switch_cpu_tick = now_time, now_tick

    # first switch, nothing to record
    if None in (then_time, then_tick):
        return

    if origin is gevent.hub.get_hub():
        return

    elapsed_ms = now_time - then_time
    elapsed_ticks = now_tick - then_tick
    if elapsed_ms <= threshold_ms:
        return

    log_fn(timing=elapsed_ms, value=elapsed_ticks, reason=trace_info)  # log extra information e.g. stack frames