| 摘要 |
A memory space for use in a packet-based network device such as a router or switch has a multiplicity of addressable memory locations 23 for the storage of data packets T1, T2, T3 etc. A write pointer 31 and read pointer 32 progressively define where data is to be written to and read from the memory space, and an ageing clock defines a succession of intervals. A further discard pointer and optionally a current pointer are generated. For each interval the current pointer corresponds to an immediately previous value of the write pointer, and the discard pointer corresponds to an immediately previous value of the current pointer so that the portion of memory space between the discard pointer and the read pointer denotes data which has been in the memory space for at least two intervals. This data is stale data which can be discarded with no risk of becoming valid again. |
