Hewlett-Packard Development Company, L.p.

Mallikarjun Chadalapaka

Paul R Culley

Jeffrey R Hilland

David J Garcia

Randolph B Haagens

Jeffrey Clifford Mogul

Michael R Krause

Dwight L Barron

Richard Fitzhugh Wrenn

James G Wendt

Richard J Wagner

Randy Haagens

The disclosed embodiments relate to an apparatus and method for acknowledging a data transfer. The first protocol may generate a request for a data transfer. The second protocol may receive the request for a data transfer from the first protocol. With the request, the second protocol may determine if the request for the data transfer contains a request for acknowledgement of completion of the data transfer. The second protocol may send a request corresponding to the request for data transfer to a third protocol. If the request for data transfer does contain a request for acknowledgement of completion of the data transfer, then the second protocol may set a variable in memory to wait for an event to correspond to the completion of the request and send an acknowledgement to the first protocol upon the occurrence of the event.

Method and apparatus for acknowledging a request for data transfer

The disclosed embodiments relate to an apparatus and method for managing flow control of a data transfer. An apparatus according to embodiments of the present invention may comprise a first protocol associated with a plurality of receive buffers, a second protocol adapted to manage the plurality of receive buffers for the first protocol, and a third protocol that determines whether one of the plurality of receive buffers is available for a data packet and (a) if one of the plurality of receive buffers is available, permits an acknowledgement packet to be sent to a node that sent the data packet, and (b) if one of the plurality of receive buffers is unavailable, drops the data packet, notifies the second protocol regarding the unavailability of the plurality of receive buffers, and withholds the acknowledgement packet.

Method and apparatus for handling flow control for a data transfer

A system and method for detecting path failure in a network are described. The system and method include a network interface which receives packets over particular connections, and an agent able to monitor the network interface and start a no-traffic timer for each particular connection when a packet is received on the connection. The agent is further able, when the no-traffic timer expires, to check for outgoing data on the particular connection, and compare a count of previously sent test packets against a limit. If the count is below the limit the agent sends a new test packet on the particular connection, the test packet provides an indication of the state of a network path associated with the particular connection. If the count is above the limit the agent initiates failover procedures for the associated path.

Fast detection of path failure for TCP

An apparatus employs a work request list to access a memory device. The apparatus comprises an upper layer protocol that generates the work request list comprising a plurality of work requests, the work request list having an attribute that indicates the number of the plurality of work requests in the work request list. The apparatus additionally comprises an interface that is adapted to receive the work request list and individually enqueue the plurality of work requests.

Method and apparatus for implementing work request lists

The disclosed embodiments relate to an optimized memory registration mechanism that may comprise an upper layer protocol that associates I/O buffers with memory regions and that manages steering tags. The memory regions may be associated with a translation page table. The upper layer protocol may allocate one of the steering tags associated with at least one of the memory regions for a memory operation.

Method and apparatus for accessing a memory

An efficient technique for performing remote asynchronous mirroring includes receiving a stream of command requests, performing the requested commands, relaying the requested commands to a target while embedding an explicitly-defined or implied task precedence graph in the relayed commands to enable increased concurrency in tasks performed by the target.

Command management using task attributes

The disclosed embodiments relate to a queuing mechanism that may comprise a shared receive queue having a plurality of buffers. The queuing mechanism may also comprise a plurality of queue pairs, each of the plurality of queue pairs having a receive queue that comprises at least one of the plurality of buffers.

Shared receive queues

The present invention is generally directed to a system and method for virtualizing storage in a networked system. In accordance with one aspect of the invention, in a system having an initiator and at least one storage device, an inventive method determines, based upon a SCSI command received by a manager from the initiator, which of the data storage devices are implicated by the SCSI command. The method then forms an iSCSI command that is sent from the manager to each of the implicated storage devices, and receives at the manager an iSCSI response from each of implicated storage devices, after each of the storage devices has completed its implicated data transactions with the initiator. Finally, the method forms a SCSI response that is sent by the manager to the initiator. A corresponding system is also provided.

Growing community of inventors

Roseville, CA, United States of America

Mallikarjun Chadalapaka