func CollectProcessMetrics(refresh time.Duration) {
	if !Enabled {
		return
	}
	memstats := make([]*runtime.MemStats, 2)
	diskstats := make([]*DiskStats, 2)
	for i := 0; i < len(memstats); i++ {
		memstats[i] = new(runtime.MemStats)
		diskstats[i] = new(DiskStats)
	}
	memAllocs := GetOrRegisterMeter("system/memory/allocs", DefaultRegistry)
	memFrees := GetOrRegisterMeter("system/memory/frees", DefaultRegistry)
	memInuse := GetOrRegisterMeter("system/memory/inuse", DefaultRegistry)
	memPauses := GetOrRegisterMeter("system/memory/pauses", DefaultRegistry)
	var diskReads, diskReadBytes, diskWrites, diskWriteBytes Meter
	var diskReadBytesCounter, diskWriteBytesCounter Counter
	if err := ReadDiskStats(diskstats[0]); err == nil {
		diskReads = GetOrRegisterMeter("system/disk/readcount", DefaultRegistry)
		diskReadBytes = GetOrRegisterMeter("system/disk/readdata", DefaultRegistry)
		diskReadBytesCounter = GetOrRegisterCounter("system/disk/readbytes", DefaultRegistry)
		diskWrites = GetOrRegisterMeter("system/disk/writecount", DefaultRegistry)
		diskWriteBytes = GetOrRegisterMeter("system/disk/writedata", DefaultRegistry)
		diskWriteBytesCounter = GetOrRegisterCounter("system/disk/writebytes", DefaultRegistry)
	} else {
		log.Debug("Failed to read disk metrics", "err", err)
	}
	for i := 1; ; i++ {
		location1 := i % 2
		location2 := (i - 1) % 2
		runtime.ReadMemStats(memstats[location1])
		memAllocs.Mark(int64(memstats[location1].Mallocs - memstats[location2].Mallocs))
		memFrees.Mark(int64(memstats[location1].Frees - memstats[location2].Frees))
		memInuse.Mark(int64(memstats[location1].Alloc - memstats[location2].Alloc))
		memPauses.Mark(int64(memstats[location1].PauseTotalNs - memstats[location2].PauseTotalNs))
		if ReadDiskStats(diskstats[location1]) == nil {
			diskReads.Mark(diskstats[location1].ReadCount - diskstats[location2].ReadCount)
			diskReadBytes.Mark(diskstats[location1].ReadBytes - diskstats[location2].ReadBytes)
			diskWrites.Mark(diskstats[location1].WriteCount - diskstats[location2].WriteCount)
			diskWriteBytes.Mark(diskstats[location1].WriteBytes - diskstats[location2].WriteBytes)
			diskReadBytesCounter.Inc(diskstats[location1].ReadBytes - diskstats[location2].ReadBytes)
			diskWriteBytesCounter.Inc(diskstats[location1].WriteBytes - diskstats[location2].WriteBytes)
		}
		time.Sleep(refresh)
	}
}
CollectProcessMetrics periodically collects various metrics about the running
process.
package metrics
import (
	"os"
	"runtime"
	"strings"
	"time"
	"github.com/dappledger/AnnChain/eth/log"
)
var Enabled bool = false
const MetricsEnabledFlag = "metrics"
const DashboardEnabledFlag = "dashboard"
func init() {
	for _, arg := range os.Args {
		if flag := strings.TrimLeft(arg, "-"); flag == MetricsEnabledFlag || flag == DashboardEnabledFlag {
			log.Info("Enabling metrics collection")
			Enabled = true
		}
	}
}