This read-only integer reports the kilobytes of memory that can be used for Packet Memory on the switch, i.e., the buffer memory available for holding packets such as broadcast traffic awaiting forwarding. An admin uses this as context when configuring broadcast-storm thresholds like cpqn52nnBcastPktCeiling, since those thresholds are meaningful only relative to this total packet buffer capacity. For example, an admin setting a broadcast packet ceiling would first check this value to make sure the configured threshold is a sensible fraction of total available packet memory.