Abstract: Methods and systems for improved management of power allocation among a plurality of devices coupled to a controller. The controller and devices exchange messages to request, grant, and release allocations of power from a common power supply. In some embodiments, the controller may be a SAS/SATA controller and the messages exchanged may be SAS/SATA frames and/or primitives. In exemplary embodiments, the messages may request/grant a particular amount of power for each of one or more voltage levels provided by the power supply. In other exemplary embodiments, the messages may designate the duration of time during which the requesting device may utilize the allocated power. A power status message from the device to the controller may indicate a change in the power consumption by the device. Responsive to the power status message the controller may re-allocate power previously allocated to a device that has completed use thereof.

Abstract: Methods and systems for encoding and/or decoding digital signals representing serial attached SCSI (SAS) out of band (OOB) signals exchanged over an optical communication between two SAS devices. A SAS OOB signal to be transmitted from a first SAS device to a second SAS device is first encoded as a digitally encoded signal representing the analog SAS OOB signal and then transmitted over an optical communication medium to another SAS device. A receiving SAS device coupled to an optical communication medium decodes a received digitally encoded signal to detect a received, encoded SAS OOB signal and processes the received SAS OOB signal when receipt is detected. The digitally encoded signal may comprise an idle word portion and a burst word portion to represent various SAS OOB signals. Further, the digitally encoded signal may be precomputed in a variety of disparity forms and stored in a memory for lookup and retrieval.

Abstract: Methods and systems for communication between two storage controllers. A first storage controller specifies a special frame indicator in a frame of a protocol that is also used by a first storage controller to send a storage command to a storage device. The first storage controller transmits the frame to a second storage controller such that the frame comprises data in a payload field of the frame.

Abstract: Methods and apparatus for improved performance in communications with a SATA target device. Features and aspects hereof provide for continuing DMA transfers from a storage controller (e.g., a SATA host or a SAS/STP initiator) to a SATA target device without regard to receipt of DMA ACTIVATE Frame Information Structures (FIS). Logic to implement these features may be provided by bridge logic within an enhanced SAS expander coupled with an enhanced SAS/STP initiator or may be provided by suitable logic in an enhanced SATA host coupled directly with an enhanced SATA target device. By continuing DMA transfer of data from the initiator/host to the SATA target device without regard to receipt of a DMA ACTIVATE FIS, more of the available bandwidth of the SAS/SATA communication link may be utilized. Other standard features of the SAS/SATA protocols provide for flow control to prevent overrun of the SATA target device's buffers.

Abstract: Methods and apparatus for improved performance in communications between a SAS/STP initiator device and a plurality of SATA storage devices coupled with the initiator through an enhanced switching device. The switching device is enhanced in accordance with features and aspects hereof to receive a DMA SETUP FIS from a SATA storage device and to transmit multiple modified DMA SETUP FISs to the initiator where each modified DMA SETUP FIS comprises a subcount less than the maximum count in the received DMA SETUP FIS.

Abstract: A system is disclosed that facilitates creation of a web-based user interface which obtains user profile information from a database, gathers information from one or more users regarding product characteristics, correlates the user responses, performs statistical analysis of the user responses and presents the statistical analysis in a user comprehendible manner. The system also stores statistical ratings in a database correlated to a particular product or service. Ratings are provided to a user from the database based on a particular product or service, and the database can be queried to retrieve one or more user profiles that have rated a product of interest to the current use.

Abstract: A system for sending large Command Descriptor Block (CDB) structures in a serial attached SCSI (SAS) controller includes a CDB Transmit Block, a CDB Memory, a Context Memory, a Direct Memory Access (DMA) Queue, a Transmit DMA Engine, and a SAS Interface. The CDB Transmit Block receives one or more Message Frames. If the CDB is small (32 bytes or less), the CDB Transmit Block reads data from the Message Frame and transmits a SAS Command Frame over the SAS interface. If the CDB is large (33 bytes or more), the CDB Transmit Block places a large CDB entry into the DMA Queue. The Transmit DMA Engine receives the large CDB entry from the DMA queue, utilizes an address pointer from the Message Frame to the CDB Memory to fetch large CDB information into a DMA buffer, and transmits a SAS Command Frame over the SAS interface.

Abstract: Methods and structures for assuring proper sequencing of processing of SAS frames received over multiple physical ports of a SAS wide port. A frame scheduler element is communicatively coupled with a SAS transport layer and with a corresponding plurality of link layers operable as a SAS wide port. The frame scheduler receives a request from the transport layer to locate or select a next received frame for further processing. The frame scheduler interacts with the plurality of link layer processing elements having received frames stored within to locate the link layer that has the requested next frame. The frame scheduler then coordinates operation of that link layer and the transport layer to effectuate the transfer of the required next frame.

Abstract: The present invention is directed to a system and method for emulating a serial small computer system interface (SAS) connection for direct attached serial advanced technology attachment (SATA) communication are disclosed. A system in accordance with the present invention includes a host controller. The host controller includes a physical interface for accepting at least one of a SAS connection or a direct attached SATA device. A common interface logic configured to receive SAS communications and SATA communications having a SAS emulated connection is included in the host controller. An emulation logic is communicatively coupled to the common interface logic. The emulation logic being configured to determine a value of a ConnectedSata signal based on the state of a SATA link state machine.

Abstract: Apparatus and method for managing power consumption of circuits within a Serial Attached SCSI (SAS) device. A SAS device having a plurality of PHY logic circuits includes a queue manager and a power manager. The queue manager is operable to determine a current workload based on queued entries for the plurality of PHY logic circuits. Based on the current workload, the power manager is operable to set identified ones of the plurality of PHY logic circuits into a low power mode. In some embodiments, PHY logic circuits may be restored to full power operation responsive to changes in the current workload and/or responsive to receipt of a signal from another SAS device coupled to the SAS device. In other embodiments the power manager is further operable to manage power consumption of link and/or DMA logic circuits of the SAS device.

Abstract: Methods and systems for improved management of power allocation among a plurality of devices coupled to a controller. The controller and devices exchange messages to request, grant, and release allocations of power from a common power supply. In some embodiments, the controller may be a SAS/SATA controller and the messages exchanged may be SAS/SATA frames and/or primitives. In exemplary embodiments, the messages may request/grant a particular amount of power for each of one or more voltage levels provided by the power supply. In other exemplary embodiments, the messages may designate the duration of time during which the requesting device may utilize the allocated power. A power status message from the device to the controller may indicate a change in the power consumption by the device. Responsive to the power status message the controller may re-allocate power previously allocated to a device that has completed use thereof.

Abstract: Methods and systems for encoding and/or decoding digital signals representing serial attached SCSI (SAS) out of band (OOB) signals exchanged over an optical communication between two SAS devices. A SAS OOB signal to be transmitted from a first SAS device to a second SAS device is first encoded as a digitally encoded signal representing the analog SAS OOB signal and then transmitted over an optical communication medium to another SAS device. A receiving SAS device coupled to an optical communication medium decodes a received digitally encoded signal to detect a received, encoded SAS OOB signal and processes the received SAS OOB signal when receipt is detected. The digitally encoded signal may comprise an idle word portion and a burst word portion to represent various SAS OOB signals. Further, the digitally encoded signal may be precomputed in a variety of disparity forms and stored in a memory for lookup and retrieval.

Abstract: Methods and systems are provided for managing power allocation to a SAS target coupled with a SAS initiator through a SAS expander. The expander exchanges messages with the target to manage the power allocation to the target. The target transmits a power request message through the expander to the initiator. In some embodiments, the initiator transmits a power request received message to the expander. The expander may then transmit a power grant message to the target in response to receiving the power request received message. In other embodiments, the expander monitors the messages transmitted from the target to the initiator. The expander may then transmit a power grant message to the target in response to the expander monitoring the power request message.

Abstract: A system for sending large Command Descriptor Block (CDB) structures in a serial attached SCSI (SAS) controller includes a CDB Transmit Block, a CDB Memory, a Context Memory, a Direct Memory Access (DMA) Queue, a Transmit DMA Engine, and a SAS Interface. The CDB Transmit Block receives one or more Message Frames. If the CDB is small (32 bytes or less), the CDB Transmit Block reads data from the Message Frame and transmits a SAS Command Frame over the SAS interface. If the CDB is large (33 bytes or more), the CDB Transmit Block places a large CDB entry into the DMA Queue. The Transmit DMA Engine receives the large CDB entry from the DMA queue, utilizes an address pointer from the Message Frame to the CDB Memory to fetch large CDB information into a DMA buffer, and transmits a SAS Command Frame over the SAS interface.

Abstract: Methods and systems for communication between two storage controllers. A first storage controller specifies a special frame indicator in a frame of a protocol that is also used by a first storage controller to send a storage command to a storage device. The first storage controller transmits the frame to a second storage controller such that the frame comprises data in a payload field of the frame.

Abstract: Methods and associated structure to assure correct order in delivery of SATA frames over a SAS wide port. In one aspect hereof, new connection requests from a SATA device are rejected until prior frames residing in receive buffers of the SAS/SATA controller are properly processed. In another aspect, when a device is already connected to the controller, the SAS/SATA controller may prevent return of a receiver ready primitive in response to a transmitter ready primitive until previously received frames are removed from the receive buffers.

Abstract: Apparatus and methods for enabling multiple, unidirectional, virtual connections between a first SAS device and multiple other SAS devices in a SAS domain. An enhanced first SAS device may be substantially simultaneously coupled to each of two other SAS devices through one or more appropriately enhanced SAS expanders to allow substantially simultaneous unidirectional virtual connections from the first SAS device to both of the second and third SAS devices. Each virtual connection is, in essence, a half-duplex connection such that the first device is transmitting information to a second SAS device substantially simultaneous with the first device receiving information from a third SAS device. The enhancements are provided in a manner to allow backward compatibility with current SAS specifications for connectivity among devices not suitably enhanced in accordance with features and aspects hereof (e.g., with legacy devices).

Abstract: A system and method for automatically analyzing virtual machine bytecode of a software application and adding additional bytecode operable to determine information regarding network communication performed by the software application are described. According to one embodiment of the method, program code of a software application may be received, wherein the program code includes bytecode for a virtual machine. The bytecode may be automatically analyzed to detect network communication functionality. The method may operate to automatically add additional bytecode to the bytecode of the software application, where the added bytecode is operable to determine information regarding the network communication.

Abstract: A system and method for automatically modifying a native code module accessed in a user software application are described herein. The user software application may include virtual machine bytecode. Access to the native code module may be detected during execution of the virtual machine bytecode. The native code module may be automatically modified by adding instrumentation code to determine various types of information regarding execution of the native code module, and the access may be directed to the modified native code module.

Abstract: A system and method for automatically analyzing virtual machine bytecode of a software application and adding additional bytecode operable to determine information regarding database access performed by the software application are described. According to one embodiment of the method, program code of a software application may be received, wherein the program code includes bytecode for a virtual machine. The bytecode may be automatically analyzed to detect access to a database. The method may operate to automatically add additional bytecode to the bytecode of the software application, where the added bytecode is operable to determine information regarding the access to the database.