func (t *tierMetrics) logSuccess(tier string) {
	t.Lock()
	defer t.Unlock()

	stat := t.requestsCount[tier]
	stat.success++
	t.requestsCount[tier] = stat
}

func (t *tierMetrics) logFailure(tier string) {
	t.Lock()
	defer t.Unlock()

	stat := t.requestsCount[tier]
	stat.failure++
	t.requestsCount[tier] = stat
}

var (
	// {minio_node}_{tier}_{ttlb_seconds_distribution}

	inShutdown      uint32        // indicates whether the server is in shutdown or not
	requestCount    int32         // counter holds no. of request in progress.
}

// GetRequestCount - returns number of request in progress.
func (srv *Server) GetRequestCount() int {
	return int(atomic.LoadInt32(&srv.requestCount))
}

// Init - init HTTP server