unsafe.Offsetof(profBuf{}.overflow),
	unsafe.Offsetof(profBuf{}.overflowTime),
	unsafe.Offsetof(heapStatsDelta{}.tinyAllocCount),
	unsafe.Offsetof(heapStatsDelta{}.smallAllocCount),
	unsafe.Offsetof(heapStatsDelta{}.smallFreeCount),
	unsafe.Offsetof(heapStatsDelta{}.largeAlloc),
	unsafe.Offsetof(heapStatsDelta{}.largeAllocCount),
	unsafe.Offsetof(heapStatsDelta{}.largeFree),
	unsafe.Offsetof(heapStatsDelta{}.largeFreeCount),

	for i := range b.smallAllocCount {
		a.smallAllocCount[i] += b.smallAllocCount[i]
	}
	a.largeFree += b.largeFree
	a.largeFreeCount += b.largeFreeCount
	for i := range b.smallFreeCount {
		a.smallFreeCount[i] += b.smallFreeCount[i]
	}
}

// consistentHeapStats represents a set of various memory statistics
// whose updates must be viewed completely to get a consistent
// state of the world.
//

		// Collect per-sizeclass free stats.
		var smallFree uint64
		for i := 0; i < _NumSizeClasses; i++ {
			slow.Frees += m.smallFreeCount[i]
			bySize[i].Frees += m.smallFreeCount[i]
			bySize[i].Mallocs += m.smallFreeCount[i]
			smallFree += m.smallFreeCount[i] * uint64(class_to_size[i])
		}
		slow.Frees += m.tinyAllocCount + m.largeFreeCount
		slow.Mallocs += slow.Frees

				// Cut off the first index which is ostensibly for size class 0,
				// but large objects are tracked separately so it's actually unused.
				for i, count := range in.heapStats.smallFreeCount[1:] {
					hist.counts[i] = count
				}
			},
		},
		"/gc/heap/frees:bytes": {
			deps: makeStatDepSet(heapStatsDep),
			compute: func(in *statAggregate, out *metricValue) {

			// wasn't totally filled, but then swept, still has all of its
			// free slots zeroed.
			s.needzero = 1
			stats := memstats.heapStats.acquire()
			atomic.Xadd64(&stats.smallFreeCount[spc.sizeclass()], int64(nfreed))
			memstats.heapStats.release()

			// Count the frees in the inconsistent, internal stats.
			gcController.totalFree.Add(int64(nfreed) * int64(s.elemsize))
		}
		if !preserve {