if (!ev_is_active(&gc_timer)) {

ev_timer_start(EV_DEFAULT_UC_ &gc_timer);

ev_unref(EV_DEFAULT_UC);

}

if (ev_is_active(&gc_timer)) {

ev_ref(EV_DEFAULT_UC);

ev_timer_stop(EV_DEFAULT_UC_ &gc_timer);

}

assert(watcher == &gc_idle);

assert(revents == EV_IDLE);

//fprintf(stderr, "idle\n");

if (V8::IdleNotification()) {

ev_idle_stop(EV_A_ watcher);

StopGCTimer();

}

assert(watcher == &gc_check);

assert(revents == EV_CHECK);

tick_times[tick_time_head] = ev_now(EV_DEFAULT_UC);

tick_time_head = (tick_time_head + 1) % RPM_SAMPLES;

StartGCTimer();

for (int i = 0; i < (int)(GC_WAIT_TIME/FAST_TICK); i++) {

double d = TICK_TIME(i+1) - TICK_TIME(i+2);

//printf("d = %f\n", d);

// If in the last 5 ticks the difference between

// ticks was less than 0.7 seconds, then continue.

if (d < FAST_TICK) {

//printf("---\n");

return;

}

}

// Otherwise start the gc!

//fprintf(stderr, "start idle 2\n");

ev_idle_start(EV_A_ &gc_idle);

HandleScope scope;

need_tick_cb = true;

// TODO: this tick_spinner shouldn't be necessary. An ev_prepare should be

// sufficent, the problem is only in the case of the very last "tick" -

// there is nothing left to do in the event loop and libev will exit. The

// ev_prepare callback isn't called before exiting. Thus we start this

// tick_spinner to keep the event loop alive long enough to handle it.

ev_idle_start(EV_DEFAULT_UC_ &tick_spinner);

return Undefined();

// Avoid entering a V8 scope.

if (!need_tick_cb) return;

need_tick_cb = false;

ev_idle_stop(EV_DEFAULT_UC_ &tick_spinner);

HandleScope scope;

if (tick_callback_sym.IsEmpty()) {

// Lazily set the symbol

tick_callback_sym =

Persistent<String>::New(String::NewSymbol("_tickCallback"));

}

Local<Value> cb_v = process->Get(tick_callback_sym);

if (!cb_v->IsFunction()) return;

Local<Function> cb = Local<Function>::Cast(cb_v);

TryCatch try_catch;

cb->Call(process, 0, NULL);

if (try_catch.HasCaught()) {

FatalException(try_catch);

}

assert(watcher == &prepare_tick_watcher);

assert(revents == EV_PREPARE);

Tick();

assert(watcher == &check_tick_watcher);

assert(revents == EV_CHECK);

Tick();

assert(watcher == &eio_poller);

assert(revents == EV_IDLE);

//printf("eio_poller\n");

if (eio_poll() != -1) {

//printf("eio_poller stop\n");

ev_idle_stop(EV_DEFAULT_UC_ watcher);

}

assert(watcher == &eio_want_poll_notifier);

assert(revents == EV_ASYNC);

//printf("want poll notifier\n");

if (eio_poll() == -1) {

//printf("eio_poller start\n");

ev_idle_start(EV_DEFAULT_UC_ &eio_poller);

}

assert(watcher == &eio_done_poll_notifier);

assert(revents == EV_ASYNC);

//printf("done poll notifier\n");

if (eio_poll() != -1) {

//printf("eio_poller stop\n");

ev_idle_stop(EV_DEFAULT_UC_ &eio_poller);

}

// Signal the main thread that we should stop calling eio_poll().

// from the idle watcher.

ev_async_send(EV_DEFAULT_UC_ &eio_done_poll_notifier);