},
		"/memory/classes/metadata/mcache/free:bytes": {
			deps: makeStatDepSet(sysStatsDep),
			compute: func(in *statAggregate, out *metricValue) {
				out.kind = metricKindUint64
				out.scalar = in.sysStats.mCacheSys - in.sysStats.mCacheInUse
			},
		},
		"/memory/classes/metadata/mcache/inuse:bytes": {
			deps: makeStatDepSet(sysStatsDep),
			compute: func(in *statAggregate, out *metricValue) {
				out.kind = metricKindUint64

		"StackInuse": {nz, le(1e10)}, "StackSys": {nz, le(1e10)},
		"MSpanInuse": {nz, le(1e10)}, "MSpanSys": {nz, le(1e10)},
		"MCacheInuse": {nz, le(1e10)}, "MCacheSys": {nz, le(1e10)},
		"BuckHashSys": {nz, le(1e10)}, "GCSys": {nz, le(1e10)}, "OtherSys": {nz, le(1e10)},
		"NextGC": {nz, le(1e10)}, "LastGC": {nz},
		"PauseTotalNs": {le(1e11)}, "PauseNs": nil, "PauseEnd": nil,

	// structures.
	MSpanSys uint64

	// MCacheInuse is bytes of allocated mcache structures.
	MCacheInuse uint64

	// MCacheSys is bytes of memory obtained from the OS for
	// mcache structures.
	MCacheSys uint64

	// BuckHashSys is bytes of memory in profiling bucket hash tables.
	BuckHashSys uint64

	// GCSys is bytes of memory in garbage collection metadata.

	dumpint(m.HeapInuse)
	dumpint(m.HeapReleased)
	dumpint(m.HeapObjects)
	dumpint(m.StackInuse)
	dumpint(m.StackSys)
	dumpint(m.MSpanInuse)
	dumpint(m.MSpanSys)
	dumpint(m.MCacheInuse)
	dumpint(m.MCacheSys)
	dumpint(m.BuckHashSys)
	dumpint(m.GCSys)
	dumpint(m.OtherSys)
	dumpint(m.NextGC)
	dumpint(m.LastGC)
	dumpint(m.PauseTotalNs)
	for i := 0; i < 256; i++ {
		dumpint(m.PauseNs[i])
	}

	fmt.Fprintf(w, "# Stack = %d / %d\n", s.StackInuse, s.StackSys)
	fmt.Fprintf(w, "# MSpan = %d / %d\n", s.MSpanInuse, s.MSpanSys)
	fmt.Fprintf(w, "# MCache = %d / %d\n", s.MCacheInuse, s.MCacheSys)
	fmt.Fprintf(w, "# BuckHashSys = %d\n", s.BuckHashSys)
	fmt.Fprintf(w, "# GCSys = %d\n", s.GCSys)
	fmt.Fprintf(w, "# OtherSys = %d\n", s.OtherSys)

	fmt.Fprintf(w, "# NextGC = %d\n", s.NextGC)

		case "/memory/classes/heap/stacks:bytes":
			checkUint64(t, name, samples[i].Value.Uint64(), mstats.StackInuse)
		case "/memory/classes/metadata/mcache/free:bytes":
			checkUint64(t, name, samples[i].Value.Uint64(), mstats.MCacheSys-mstats.MCacheInuse)
		case "/memory/classes/metadata/mcache/inuse:bytes":
			checkUint64(t, name, samples[i].Value.Uint64(), mstats.MCacheInuse)
		case "/memory/classes/metadata/mspan/free:bytes":

		{"MemStats.HeapReleased", Field, 0},
		{"MemStats.HeapSys", Field, 0},
		{"MemStats.LastGC", Field, 0},
		{"MemStats.Lookups", Field, 0},
		{"MemStats.MCacheInuse", Field, 0},
		{"MemStats.MCacheSys", Field, 0},
		{"MemStats.MSpanInuse", Field, 0},
		{"MemStats.MSpanSys", Field, 0},
		{"MemStats.Mallocs", Field, 0},
		{"MemStats.NextGC", Field, 0},
		{"MemStats.NumForcedGC", Field, 8},

pkg runtime, type MemStats struct, LastGC uint64
pkg runtime, type MemStats struct, Lookups uint64
pkg runtime, type MemStats struct, MCacheInuse uint64
pkg runtime, type MemStats struct, MCacheSys uint64
pkg runtime, type MemStats struct, MSpanInuse uint64
pkg runtime, type MemStats struct, MSpanSys uint64
pkg runtime, type MemStats struct, Mallocs uint64
pkg runtime, type MemStats struct, NextGC uint64