// and the last heap goal, which tells us by how much the heap is growing and
// shrinking. We estimate what the heap will grow to in terms of pages by taking
// this ratio and multiplying it by heapInUse at the end of the last GC, which
// allows us to account for this additional fragmentation. Note that this
// procedure makes the assumption that the degree of fragmentation won't change

// allocManual returns nil if allocation fails.
//
// allocManual adds the bytes used to *stat, which should be a
// memstats in-use field. Unlike allocations in the GC'd heap, the
// allocation does *not* count toward heapInUse.
//
// The memory backing the returned span may not be zeroed if
// span.needzero is set.
//
// allocManual must be called on the system stack because it may

		traceRelease(trace)
	}

	// all done
	mp.preemptoff = ""

	if gcphase != _GCoff {
		throw("gc done but gcphase != _GCoff")
	}

	// Record heapInUse for scavenger.
	memstats.lastHeapInUse = gcController.heapInUse.load()

	// Update GC trigger and pacing, as well as downstream consumers
	// of this pacing information, for the next cycle.
	systemstack(gcControllerCommit)

	//
	// Because the runtime is responsible for managing a memory limit, it's
	// useful to couple these stats more tightly to the gcController, which
	// is intimately connected to how that memory limit is maintained.
	heapInUse    sysMemStat    // bytes in mSpanInUse spans
	heapReleased sysMemStat    // bytes released to the OS
	heapFree     sysMemStat    // bytes not in any span, but not released to the OS