Hewlett-packard Development Company, L.p.

Hewlett-packard Company

Chiaro Networks Ltd

Paul F Vogel

Bryan D Hornung

Gregory S Palmer

Tony M Brewer

Michael K Dugan

Jim Kleiner

Keith W Shaw

A system for moving checksums within memory utilizes a plurality of memory systems and a system manager. A first memory system has a first memory location that is correlated with a checksum indicator. The checksum indicator identifies the memory system that is storing the checksum of the value presently stored at the first location. The system manager dynamically moves the checksum to a destination memory location and updates the checksum indicator such that the checksum indicator identifies the memory system of the destination memory location. While the checksum is being moved, checksum updates may occur to the memory location from which the checksum was moved. Thus, after moving the checksum, the system manager updates the checksum with the value stored at the location from which the checksum was moved. As a result, the checksum stored in the checksum destination location should be sufficiently updated to enable data recovery.

System and method for dynamically moving checksums to different memory locations

Hardware interconnected around multiple packet forwarding engines prepends sequence numbers to packets going into multiple forwarding engines through parallel paths, After processing by the multiple forwarding engines, packets are reordered using queues and a packet ordering mechanism, such that the sequence numbers are put back into their original prepended order. Exception packets flowing through the forwarding engines do not follow a conventional fast path, but are processed off-line and emerge from the forwarding engines out of order relative to fast path packets. These exception packets are marked, such that after they exit the forwarding engines, they are ordered among themselves independent of conventional fast path packets. Viewed externally, all exception packets are ordered across all multiple forwarding engines independent of the fast path packets.

System and method for router packet control and ordering

A data storage system utilizes a plurality of memory systems, at least one processor, and a mapping system. Each of the memory systems has memory and a memory controller for storing and retrieving data. The processor transmits requests for writing data values. These requests include bus addresses. The mapping system maps the bus addresses into memory addresses. The mapping system maps consecutive bus addresses such that the memory addresses mapped from the consecutive bus addresses are interleaved across a plurality of the memory systems. In response to the foregoing requests from the processor, the mapping system identifies checksum system identifiers that identify locations where checksum values to be updated based on the aforementioned data values are stored. The checksum system identifiers preferably identify each of the plurality of mapping systems so that the checksum identifiers and, therefore, the checksum updates that occur based on these checksum system identifiers are interleaved across these memory systems.

System and method for mapping bus addresses to memory locations utilizing access keys and checksums

A system for building checksums efficiently builds a checksum of various data values that are stored in different memory units of a computer system. During the checksum build process, data stores to the memory locations storing the various data values are enabled, thereby enabling the checksum to be built without significantly impacting the performance of the computer system.

System and method for building a checksum

A system for storing and retrieving data utilizes a plurality of memory units having memory locations for storing data values. A checksum of a plurality of the data values in a particular checksum set is maintained in one of the memory locations. One of the plurality of data values can be recovered by combining each of the remaining plurality of data values with the checksum. After retrieving one of the plurality of data values during the data recovery process, steps are taken to ensure that any further attempts to access the location of the retrieved data value do not cause an update to the checksum. Therefore, the locations storing the data values of the checksum set may be accessed (e.g., read from or written to) during the data recovery process without causing errors to the data recovery process.

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Garland, TX, United States of America

Paul F Vogel