func (s *Stat) Init(label []byte, value float64) *Stat {
	s.label = s.label[:0]  
	s.label = append(s.label, label...)
	s.value = value
	s.isWarm = false
	return s
}
Init safely initializes a Stat while minimizing heap allocations.
package query
import (
	"fmt"
	"io"
	"sort"
	"sync"
	"github.com/HdrHistogram/hdrhistogram-go"
)
var (
	hdrScaleFactor = 1e3
)
type Stat struct {
	label     []byte
	value     float64
	isWarm    bool
	isPartial bool
}
var statPool = &sync.Pool{
	New: func() interface{} {
		return &Stat{
			label: make([]byte, 0, 1024),
			value: 0.0,
		}
	},
}
func GetStat() *Stat {
	return statPool.Get().(*Stat).reset()
}
func GetPartialStat() *Stat {
	s := GetStat()
	s.isPartial = true
	return s
}