func (v *Counter) Add(delta int64) {
	if delta < 0 {
		log.Warn("[stats] Adding a negative value to a counter, %v should be a gauge instead", v)
	}
	v.i.Add(delta)
}
Add adds the provided value to the Counter.
package stats
import (
	"strconv"
	"github.com/nooncall/shazam/log"
	"github.com/nooncall/shazam/util/sync2"
)
type Counter struct {
	i    sync2.AtomicInt64
	help string
}
func NewCounter(name string, help string) *Counter {
	v := &Counter{help: help}
	if name != "" {
		publish(name, v)
	}
	return v
}