cpu 100% problem #126

void TracerImpl::run() {
  void* got_tag;
  bool ok = false;
  while (true) {
    // TODO(shikugawa): cleanup evloop handler.
    if (cds_timer_ != nullptr && cds_timer_->check()) {
      cdsRequest();
    }

    grpc::CompletionQueue::NextStatus status = cq_.AsyncNext(
        &got_tag, &ok, gpr_time_from_nanos(0, GPR_CLOCK_REALTIME));

  void* got_tag;
  bool ok = false;
  while (true) {
    // TODO(shikugawa): cleanup evloop handler.
    if (cds_timer_ != nullptr && cds_timer_->check()) {
      cdsRequest();
    }

#if 0
    grpc::CompletionQueue::NextStatus status = cq_.AsyncNext(
        &got_tag, &ok, gpr_time_from_nanos(0, GPR_CLOCK_REALTIME));
#endif
    grpc::CompletionQueue::NextStatus status = cq_.AsyncNext(
        &got_tag, &ok, gpr_time_from_nanos(100000000, GPR_TIMESPAN));
    switch (status) {
      case grpc::CompletionQueue::TIMEOUT:
        continue;
      case grpc::CompletionQueue::SHUTDOWN:
        return;
      case grpc::CompletionQueue::GOT_EVENT:
        break;
    }
    static_cast<StreamCallbackTag*>(got_tag)->callback(!ok);
  }
}