const runtime.userArenaChunkPages

4 uses

	runtime (current package)
		arena.go#L196: 	userArenaChunkPages = userArenaChunkBytes / pageSize
		arena.go#L206: 	if userArenaChunkPages*pageSize != userArenaChunkBytes {
		arena.go#L1023: 				s.init(uintptr(v)+i, userArenaChunkPages)
		arena.go#L1049: 	h.initSpan(s, spanAllocHeap, spc, base, userArenaChunkPages)