Abstract: Controlling accesses to target devices such as disk drives by modifying the duty cycle profile of those devices to improve device reliability is disclosed. The utilization of a target device is monitored, and if a device is being overused, that device is given a rest period by reserving it for a special initiator that does not send any commands to the device for a certain period of time. This reduced utilization has the effect of increasing the reliability of the target device. This period of time also adds a delay to the processing of commands for the target device being overutilized so that the device becomes less responsive. This performance penalty creates pressure on system administrators to reduce the number of commands sent to that target device and/or move data to proper devices (that can handle the high number of accesses).

Abstract: Auto-discrimination between FC and SATA devices upon insertion of a device into a port of a FAST-compatible switch is disclosed. Without user intervention, the port is able to determine the type of device attached, set the appropriate data rate in the Phy or SERDES and, in the case of FC or SATA drives, start the disk insertion process into the active switch zones. The SERDES is first initialized to FC speeds, and the receive path is searched for a receive signal. Upon detecting a receive signal, the detection circuitry then checks to see if a valid SATA Out Of Band (OOB) sequence is received. If a valid SATA OOB sequence is received, the SERDES is configured for SATA speeds and analog settings. If a valid SATA OOB sequence is not received, and instead a FC auto-negotiation process runs to completion, the SERDES remains at FC speeds.

Abstract: A system for enabling SATA drives to be utilized in FC SANs is disclosed To send SATA FISs to a SATA drive over a FC SAN, a host sends SCSI commands encapsulated in FC frames over a standard FC link to a Fibre Channel Attached SATA Tunneling (FAST) RAID controller, where the SCSI commands are de-encapsulated from the FC frames and translated to SATA FISs. The SATA FISs are thereafter encapsulated into FC frames. The IOC that performs these functions is referred to as a FAST IOC. The SATA-encapsulated FC frames are sent to multiple disk drive enclosures over another standard FC link. The FC frames are de-encapsulated by FAST switches in disk drive enclosures to retrieve the SATA FISs, and the SATA FISs are sent to the SATA drives over a SATA connection.

Abstract: A system for enabling SATA drives to be utilized in FC SANs is disclosed. To send data to a SATA drive over a FC SAN, a host sends SCSI commands encapsulated in FC frames over a standard FC link to a Fibre Channel Attached SATA Tunneling (FAST) RAID controller, where the SCSI commands are de-encapsulated from the FC frames and translated to SATA FISs. The SATA FISs are thereafter encapsulated into FC frames. The IOC that performs these functions is referred to as a FAST IOC. The SATA-encapsulated FC frames are sent to multiple disk drive enclosures over another standard FC link. The FC frames are de-encapsulated by FAST switches in disk drive enclosures to retrieve the SATA FISs, and the SATA FISs are sent to the SATA drives over a SATA connection.

Abstract: A method is disclosed for maintaining a table of recent accesses for each port for use in predicting whether a request for data from a source device is likely to be sent to a high speed or low speed destination device. The table of recent accesses lists every source device attached to that port and the speed of the destination device with the most recent access to each source device. When an OPN primitive is received at the source port, the source device is identified and used with the table of recent accesses to predict whether the destination device is likely to be high speed or low speed, and ultimately whether to send data from the source device or reject the request.

Abstract: A method for maintaining configurable and dynamically adjustable per-channel local port/bypass port access ratios in the multiple SOCs within an SPI-attached frame-based switch enclosure to improve the access fairness of devices upstream from the destination device is disclosed. A frame-based switch enclosure may include multiple SPI-attached SOCs, each SOC containing a plurality of ports, with one or more devices connected to each port and one virtual channel assigned to each port. Given a frame-based switch enclosure with N SOCs, the local port/bypass port access ratio for a particular SOC and a given virtual channel, where the particular SOC is M hops away from the SOC having a port corresponding to the given virtual channel and M>0, is 1:(N?M?1), while the local port/bypass port access ratio for the SOC (and the given virtual channel) having the port corresponding to the given virtual channel (i.e. the SOC for which M=0) is 0:0.

Abstract: Embodiments of the present invention are directed to controlling device access fairness in frame-based switches by automatically and continuously counting the number of actively communicating devices connected to each port and the type of devices connected to each port, and adjusting fairness accordingly. During a sampling window, the number of active devices and the type of devices connected to each port is determined. At the start of each fairness window, a weighted number of slots are assigned to each port based on the number of active devices connected to each port and the type of devices connected to that port. Within a single fairness window, each port is able to provide device accesses to the frame-based switch in accordance with the number of slots assigned to that port.

Abstract: A backpack for a human to carry a load utilizing an external frame to which is attached a fabric bag comprised of multiple compartments each of a cylindrical geometry where the compartments share no common fabric panels. The frame has a bottom shelf that bears the weight of the bag allowing lighter fabric to be used and also allows the backpack to stand by itself on the ground. The two outside vertical tubes of the frame are not parallel, being tapered inward towards each other at the top and also rising above the topmost compartment of the bag to provide a hanging fixture for other hiking gear. A waist belt assembly can incorporate a curved polymer insert to distribute the majority of the weight of a loaded pack on the lumbar curve of the spine. The insert is overlaid with a panel of cushioning material that can be repositioned to form the base of a camp chair.