func (r *ewmaRate) incr(incr int64) {
	atomic.AddInt64(&r.newEvents, incr)
}
func (r *ewmaRate) incr(incr int64) {
	atomic.AddInt64(&r.newEvents, incr)
}
func ( r * ewmaRate ) incr ( incr int64 ) { atomic . AddInt64 ( & r . newEvents , incr ) }
// inc counts one event.
inc counts one event .