Abstract: Bandwidth is allocated among network interfaces of, for example, a switch, router, or server among based on network packet traffic. In one example the network device has a plurality of network interfaces, a performance monitoring unit to monitor buffer events for the network interfaces and to generate an interrupt if a network interface buffer is near an overflow state, and a processor to receive the interrupt and increase a priority of the associated network interface in response thereto.

Abstract: If an input word bit includes overhead data, the input word bit is ignored. If the input word bit includes non-overhead data and the corresponding bit position in a first buffer is empty, the non-overhead data is stored in the corresponding bit position in the first buffer, and the corresponding bit position in the first buffer is marked as full. Otherwise, the non-overhead data is stored in the corresponding bit position in a second buffer, and the corresponding bit position in the second buffer is marked as full. When all bit positions in the first buffer are marked as full, the data is shifted out of the first buffer, rotated to be in data arrival sequence, and made available for further processing. Then, the data in the second buffer is transferred to the first buffer, and the bit positions in second buffer are reset to be marked as empty.

Abstract: A communication system complying with SPI-4 Phase 2 standard includes a local device, an opposing device, a first data channel to transfer payload data from the local to the opposing device, a second data channel opposed to the first data channel, and a first status channel to be able to transfer data from the local to the opposing device. The local device periodically outputs buffer status information of a data buffer for storing payload data received over the second data channel to the first status channel. Further, the local device inserts the buffer status information between the payload data according to a priority of the buffer status information in order to output the buffer status information to the first data channel. The opposing device controls to output payload data to the second data channel according to the buffer status information received over the first status channel and the first data channel.

Abstract: Certain embodiments of the invention may be found in a method and system for handling data in port bypass controllers for storage systems and may comprise receiving a data stream from a receive port bypass controller's port and buffering at least a portion of the received data stream in at least one EFIFO buffer integrated within the port bypass controller. A data rate or frequency of the received data stream may be changed by inserting at least one extended fill word in the buffered portion of the received data stream or by deleting at least one fill word from the received data stream buffered in the EFIFO buffer. The extended fill word may comprise a loop initialization primitive (LIP), a loop port bypass (LPB), a loop port enable (LPE), a not operation state (NOS), an offline state (OLS), a link reset response (LRR) and/or a link reset (LR).

Abstract: An information processor (program processing unit 1) for managing a data sequence in a fixed order comprises a direction array (reference data storage section 2) for storing a reference to each data item of the data sequence in an element of the index associated with the key to the data, and means (CPU 3) for changing all data keys referenced by elements within an arbitrary range of indexes in the direction array by the same amount, where memory contents within the range of the direction array are shifted by the number of indexes corresponding to the changed amount.

Abstract: An output buffer in a multi-threaded processor is managed to store a variable amount of output data. Parallel threads produce a variable amount of output data. A controller is configured to determine how much output buffer space is needed per thread and how many threads can execute in parallel, given the available space in the output buffer. The controller also determines where each thread writes to in the output buffer.

Abstract: A method and apparatus are disclosed for implementing STP flow control in SAS expander devices. SAS expanders are commonly used within a SAS network topology to allow multiple disk drives to connect to multiple host devices. Connections to a SATA HDD are supported using SATA Tunnelling Protocol (STP), which allows SATA traffic to be carried over a SAS network topology. Flow control in a STP connection is applied through a set of special SATA primitives, both for forward and backward flow control. A method is described herein in which STP flow control is supported without the use of a SATA link layer state machine. This allows STP flow control to be terminated on a hop-by-hop basis without knowing the data channel direction or maintaining a SATA link state machine, and while minimizing gate count.

Abstract: Method and apparatus for synchronizing a software buffer index with an unknown hardware buffer index. Specifically, a method of processing data is disclosed comprising synchronizing a software buffer index to a hardware buffer index. The method sequentially searches through a plurality of buffers containing data to find a second buffer with unprocessed data. The method is implemented when the software buffer index points to a first buffer containing processed data. Thereafter, the software buffer index is reset to the next available buffer having processed data following the second buffer.

Abstract: A method, system, and computer program product in a data processing system are disclosed for dynamically selecting software buffers for aggregation in order to optimize system performance. Data to be transferred to a device is received. The data is stored in a chain of software buffers. Current characteristics of the system are determined. Software buffers to be combined are then dynamically selected. This selection is made according to the characteristics of the system in order to maximize performance of the system.

Abstract: A client device receives streaming content from a host device. The streaming content is placed in one or more buffers prior to processing. Monitoring as to the capacity and fullness of the buffers is performed at the client device and information is sent to the host device. The host device adjusts the rate or flow of the streaming content based on the information provided by the client device.

Abstract: For an electronic apparatus in which data is transferred between a plurality of processing devices and a memory, a technique is provided which prevents the data transfer from being restricted and allows the processing devices to operate efficiently. The order of priorities of data transfer operations through channels is changed on the basis of a relation between thresholds and the amounts of data remaining respectively in FIFO buffers. This prevents the FIFO buffers from becoming empty of data, or from being filled up with data, which allows the devices to operate efficiently.

Abstract: An apparatus and method for maximizing buffer utilization in an I/O controller using credit management logic contained within the I/O controller. The credit management logic keeps track of the number of memory credits available in the I/O controller and communicates to a chipset connected to the I/O controller the amount of available memory credits. The chipset may then send an amount of data to the I/O controller equivalent to or less than the communicated available amount of memory credits to reduce the occurrence of a “retry” event. The amount of available memory credits is determined by comparing the available memory in each buffer within the I/O controller and designating that the “available” amount of memory for the I/O controller is an amount equivalent to the amount of memory contained in the buffer with the least amount of available memory. This “available” amount of I/O controller memory may then be converted into memory credits and communicated to the chipset.

Abstract: A cryptographic system (500) includes cryptographic sub-units (510) and associated input buffers (520) connected to a scheduler (530) and a reassembler (540). The scheduler (530) receives packets, where each of the packets includes one or more data blocks, and assigns each of the packets to one of the sub-units (510). The input buffers (520) temporarily store the packets from the scheduler (530). Each of the sub-units (510) performs a cryptographic operation on the data blocks from the associated input buffer (520) to form transformed blocks. The reassembler (540) receives the transformed blocks from the sub-units (510), reassembles the packets from the transformed blocks, and outputs the reassembled packets in a same order in which the packets were received by the scheduler (530).

Abstract: An interface controller connected to a read request device which performs a read request to a storage device stored with data, includes a receiving buffer which stores a read response of said storage device with respect to the read request sent from said read request device; and a control unit which performs read request authorization to said read request device on the basis of a capacity of said receiving buffer, a read request size and a read response size.

Abstract: An audio input/output control apparatus, in which the speed difference between writing speed in writing audio data to a ring buffer and reading speed in reading out the audio data under a constant speed is calculated. When a read-address is forcibly changed according to the speed difference, between the signal level of the audio data corresponding to a read-address before the change and the signal level of the audio data corresponding to a read-address after the change, an address position at which the signal level change is less than a predetermined value is determined as a read-address after the change. So, the amount of signal processing can be significantly reduced, and the quality of audio data can be maintained.

Abstract: A storage apparatus comprises: a memory for storing a processing ratio/upper limit table, which stores an upper limit number per prescribed time for input/output processing in accordance with the processing of a processing type for each of a plurality of processing types executed by a host computer; and a processor which receives an input/output request from the host computer, and executes input/output processing corresponding to the input/output request, such that input/output processing corresponding to the processing of each processing type per prescribed time falls within the upper limit number. According to this constitution, the input/output processing count per prescribed time can be properly controlled in accordance with the processing type.

Abstract: In a circuit coupled to a port of a network having a loop architecture, a read/write pointer controller provides a read and a write pointer to track transmission words stored in a FIFO array. The read/write pointer controller also provides a FIFO level indicator to track the total number of transmission words in the FIFO array. A dynamic threshold controller tracks transmission word insertions and deletions in the FIFO array for a predetermined period of time and provides a threshold level adjustment signal based on the tracked transmission word insertions and deletions and a transmission word threshold level. A FIFO level adjuster provides transmission word insert and delete commands and adjusts the threshold level of the FIFO array in response to the threshold level adjustment signal.

Abstract: Digital logic processing devices capable of reduced power consumption may be provided. A digital logic processing device may include one or more processing elements, an input FIFO for storing data, a processing unit, and a clock controller circuit. The processing unit may process data from the input FIFO and the clock controller circuit may control a clock signal supplied to the input FIFO and the processing unit. The clock controller circuit may monitor whether there is data to be transferred to the input FIFO and states of the input FIFO and the processing unit and may control the clock signal.

Abstract: A data output apparatus checks data accumulated state in the accumulating unit at a preset check interval, and changes at least one setting among an initial accumulation amount to be used as a basis for starting to output the data accumulated in the accumulating unit, an upper accumulation limit amount to be used as a basis for discarding accumulated data, and a check interval, according to a discarded state of the data based on check results. Therefore, in the data output apparatus such as an IP telephony terminal apparatus, it is possible to prevent sound interruption and limit a lowering of communication quality.

Abstract: Methods and systems are provided for reducing partial cache writes in transferring incoming data status entries from a peripheral device to a host. The methods comprise determining a lower limit on a number of available incoming data status entry positions in an incoming data status ring in the host system memory, and selectively transferring a current incoming data status entry to the host system memory using a full cache line write if the lower limit is greater than or equal to a first value. Peripheral systems are provided for providing an interface between a host computer and an external device or network, which comprise a descriptor management system adapted to determine a lower limit on a number of available incoming data status entry positions in an incoming data status ring in a host system memory, and to selectively transfer a current incoming data status entry to the host system memory using a full cache line write if the lower limit is greater than or equal to a first value.

Abstract: Provided is a data communication system including a first-in first-out (FIFO) buffer having a fixed size; a central processing unit (CPU) that writes data stored in a memory into the FIFO buffer; a modem that reads the data written by the CPU from the FIFO buffer; and a modem controller that is connected to the FIFO buffer, the CPU, and the modem, respectively, and controls the CPU such that data having a larger volume than the size of the FIFO buffer can be processed.

Abstract: A method for improving timing behavior of a processing unit in a multithreading environment is disclosed, wherein the processing unit generates data frames for an output unit by combining data from a plurality of input units, and the processed data are buffered in an output buffer between the processing unit and the output unit. The method comprises sending from the output unit to the processing unit a value corresponding to the filling of the output buffer, calculating a timer value, setting a timer with the timer value, wherein the timer calls the processing unit thread after the specified time. The timer value depends on the value corresponding to the averaged filling of the output buffer. As a result, the average filling of the output buffer is lower compared to conventional thread management, and thus the system is more flexible and reacts quicker.

Abstract: A method and system for processing out of order frames received by a host bus adapter is provided. The method includes, determining if a current frame is out of order; determining if a frame is within a range of transfer for an Exchange; and creating (or appending if not the first out-of-order frame) an out of order list if the current frame is a first out of order frame. The method also includes, determining if an entry in an out of order list has a relative offset value of zero; determining if at least one entry has a relative offset value equal to a total transfer length of an Exchange; and determining if every non-zero starting relative offset has a matching entry. The method also scans an out of order list and combines a last entry with an entry whose starting point matches the end point of the last entry.

Abstract: An integrated circuit includes a plurality of tiles. Each tile comprises a processor; a switch including switching circuitry to forward data over data paths from other tiles to the processor and to switches of other tiles; a first buffer that stores data from the switch; a memory accessible to the processor; a second buffer that stores a plurality of data words retrieved from the memory; and a multiplexer that selectively provides data to the processor from the first buffer or the second buffer based on a refill signal.

Abstract: Systems and methods for designing data structures are provided. In one embodiment, an asynchronous first-in-first-out (FIFO) data structure may include, for example, a FIFO memory having a depth d in which d is an integer and a code generator coupled to the FIFO memory. The code generator may provide, for example, a first code sequence of length 2d. The first code sequence may have a circular property and a Hamming length of one for any two consecutive codes of the first code sequence. The first code sequence may be generated from a second code sequence by removing one or more pairs of mirrored codes of the second code sequence.

Abstract: Embodiments of the present invention provide a media drive that is intended for reduction in power consumption required for serial communications to/from a host, and a power saving method thereof. In one embodiment, a HDD includes: a cache; a host interface for transferring, to a host, transfer data read out from the cache; a host interface manager that controls the execution of commands so as to generate a transfer unnecessary period during which a command and transfer data need not be exchanged with the host; and a MPU that brings a serial communication part of the host interface into a power save mode during the transfer unnecessary period. The host interface manager determines the optimum data transfer timing of transferring data from the cache to the host on the basis of a transfer rate at which data is transferred to the host, and a read rate at which data is read out from a disk into the cache.

Abstract: A method, apparatus and program storage device for managing dataflow through a processing system is disclosed. A buffer monitor maintains and monitors a buffer full threshold to control the write throughput to a data bus.

Abstract: A programmatic time-gap defect correction apparatus and method corrects errors which may go undetected by a computer system. Buffer underruns or overruns, which may incur errors in data transfers, yet remain undetected and uncorrected in a computer system, are corrected by an error avoidance module in accordance with the invention. Bytes transferred to and from buffers, used by an I/O controllers to temporarily store data while being transferred between synchronous and asynchronous devices, are counted and an error condition is forced based on the count. If the count exceeds the capacity of the buffer, an error condition is forced, thereby reducing chances that errors are incurred into the data transfer.

Abstract: A device and method for transferring data is disclosed that facilitates data transfers between devices having different clock domains. The data transfer from one device to another occurs through a First In First Out memory (FIFO). The relative number of FIFO access cycles to the FIFO is controlled to maintain a desired FIFO fullness. Setting the desired FIFO fullness to a desired value allows control of data transfer latency between devices.

Abstract: A portable memory device is provided that is capable of easy connection to a personal computer via a universal serial bus (USB) port, IEEE 1394 (i.e., firewire) or similar port. Included in the portable memory device is a compression/decompression engine capable of compressing and decompressing data. Data residing on a personal computer or other host platform is compressed by the engine and saved to the memory of the portable memory device. Compressed data is retrieved and decompressed by the engine and transmitted to the personal computer for use by the user. Embodiments of the present invention thus provide a highly convenient system and apparatus for users to access and save larger quantities of data to a relatively small device.

Abstract: The serial communication device capable of reducing the load on the CPU is provided for a system using the serial communications such as the car navigation system. The attention is focused on the control method of the serial communication, in which a DMA controller is used for the data reception in the serial communication, and a number larger than the number of data received at a time is set in advance as the number of transfers of the receive DMA controller, and further, the function to generate the timeout interrupt when data is not received for a certain period is added to the serial interface, so that the serial communication can be controlled and performed without applying the load on the CPU.

Abstract: Disclosed are a method, upstream processing node, and computer readable medium for dynamically stabilizing a stream processing system. The method includes receiving at least one computing resource allocation target. The method further includes determining that an input data flow rate of at least one upstream processing element varies. The computing resource is dynamically allocated to the upstream processing element in response to the input rate of the upstream processing element varying. Data flow is dynamically controlled between the upstream processing element and at least one downstream processing element.

Abstract: Method and system for conservatively managing store capacity available to a processor issuing stores are provided and described. In particular, a counter mechanism is utilized, whereas the counter mechanism is incremented or decremented based on the occurrence of particular events.

Abstract: This invention relates to a method and system for changing an output rate of information for a buffer (3) with a constant first output rate (R1) which receives output data from a data source (2a), where the method step comprises; halting the reception of output data from the data source (2a); outputting (4) the stored output data of the buffer (3) at the first output rate (R1) until said buffer is empty, and resuming receiving and storing of output data in the buffer (3); setting a second constant output rate (R2) as the output rate of the buffer; and commencing/starting output of the content of the buffer at the second output rate (R2) when the amount of buffered data is equal to the second constant output rate (R2) times a requested buffer-time (TB2).

Abstract: A storage subsystem includes a variable-size write buffer that temporarily stores write data received from a host system. The storage subsystem is capable of adjusting the size of the write buffer so as to vary both the performance (e.g., sustained write speed) of the storage subsystem and a risk of data loss. In one embodiment, the storage subsystem implements a command set that enables the host system to directly control the size of the write buffer. The storage subsystem may additionally or alternatively be capable of adjusting the size of the write buffer based on monitored operating conditions, such as the temperature, the stability/consistency of a power signal received from the host system, and/or the elapsed time since the storage subsystem was last powered up.

Abstract: Measuring transit time across an asynchronous first-in-first-out (FIFO) memory can include sampling an indication of a value of a read pointer of the FIFO memory at a sampling frequency that exceeds a frequency of a read clock and a write clock of the FIFO memory. An indication of a value of a write pointer of the FIFO memory can be sampled at the sampling frequency. For each sampling period, a measure of occupancy of the FIFO memory can be calculated according to a sampled pair including the indication of the value of the read pointer and the indication of the value of the write pointer. The measure of occupancy can be averaged over a predetermined number of cycles of the sampling frequency. The averaged measure of occupancy can be output as an indication of transit time across the FIFO memory.

Abstract: Described herein are methods and apparatus, including computer program products, that implement cache eviction for runtime systems. A computer program product can cause a data processing apparatus to compute a fill level of a cache memory; use a first eviction process to evict one or more of the entities in the cache memory if the fill level exceeds a first threshold but not a second threshold; use a second, distinct eviction process to evict one or more of the entities in the cache memory if the fill level exceeds the second threshold but not a third threshold; and decline subsequent requests to store additional entities in the cache memory if the fill level exceeds the third threshold.

Abstract: A method and apparatus for adaptive buffer sizing adjusts the size of the buffer at different levels using a “high water mark” to different levels for different system conditions. The high water mark is used by the buffer logic as an indication of when to assert the buffer “Full” flag. In turn, the full flag is used by the instruction fetch logic as an indication of when to stop fetching further instructions.

Abstract: A method and disc drive are disclosed that employ dynamic buffer size allocation for handling multiple data streams, such as time-sensitive audio/video data. The method involves allocating a certain amount of required buffer space for each data stream to be handled without an interruption in recording or playing back the data stream. The method further involves reallocating the amount of required buffer space for each stream including any additional stream when one or more additional streams are to be added to the total number of streams being handled. The method also involves reallocating the amount of required buffer space for each stream including those streams that remain after any of the data streams being handled are terminated.

Abstract: The exemplary embodiment of the present invention provides a storage buffer management scheme for I/O store buffers. Specifically, the storage buffer management system as described within the exemplary embodiment of the present invention is configured to comprise storage buffers that have the capability to efficiently support 128 byte or 256 byte I/O data transmission lines. The presently implemented storage buffer management scheme enables for a limited number of store buffers to be associated with a fixed number of storage state machines (i.e., queue positions) and thereafter the allowing for the matched pairs to be allocated in order to achieve maximum store throughput for varying combinations of store sizes of 128 and 256 bytes.

Abstract: A method and system for providing delay bound and prioritized packet dropping are disclosed. The system limits the size of a queue configured to deliver packets in FIFO order by a threshold based on a specified delay bound. Received packets are queued if the threshold is not exceeded. If the threshold is exceeded, a packet having a precedence level less than that of the precedence level of the received packet is dropped. If all packets in the queue have a precedence level greater than that of the packet received, then the received packet is dropped if the threshold is exceeded.

Abstract: A computer implemented method, data processing system, and computer program product for detecting circular buffer overrun in a credit-based data management system, wherein the system comprises a total credit exchange amount of at least one less than the total number of entries in a circular buffer. When data in a data item entry is processed in the circular buffer, a valid mark bit is set in the data item entry to an inactive state. A location of the data item entry previously processed is then stored. A valid mark bit of a next data item entry in the circular buffer and the valid mark bit in the data item entry previously processed are read. Responsive to a determination that the valid mark bit in the data item entry previously processed indicates the data item entry contains data to be processed, an indication may be generated that a circular buffer overflow has occurred.

Abstract: A control machine which uses a data amount stored in an FIFO as a trigger and allows a DMA transfer to be started according to a capacity of the FIFO allows a control machine for preparing for the DMA transfer to start to prepare a command and the like for the DMA transfer. The control machine for preparing for the DMA transfer issues the prepared command to a control machine for transferring DMA data, so that a process according to the command is started. At the time of the DMA transfer, a burden on a host CPU is reduced.

Abstract: A direct memory access system utilizing a local memory that stores a plurality of DMA command lists, each comprising at least one DMA command. A command queue can hold a plurality of entries, each entry comprising a pointer field and a sequence field. The pointer field points to one of the DMA command lists. The sequence field holds a sequence value. A DMA engine accesses an entry in the command queue and then accesses the DMA commands of the DMA command list pointed to by the pointer field of the accessed entry. The DMA engine performs the DMA operations specified by the accessed DMA commands. The DMA engine makes available the sequence value held in the sequence field of the accessed entry when all of the DMA commands in the accessed command list have been performed. In one embodiment, the command queue is part of the DMA engine.

Abstract: Provided is a vehicle data recording device in which detection values of an acceleration sensor 210 and an driving status detecting sensor 220 are periodically and continuously recorded in a ring buffer 120, a detection value which has already been recorded in the ring buffer 120 is recorded in a specific recording area of a recorder 130 before a new detection value is recorded in the ring buffer 120 when a recording condition is satisfied, while the new detection value is periodically recorded in another recording area of the recorder 130, and recording is performed by the recorder 130 until all detection values which have already been recorded in the ring buffer 120 when the recording condition is satisfied are entirely recorded in a specific recording area of the recorder 130.

Abstract: Various techniques for manipulating data using access states of memory, access control fields of pointers and operations, and exception raising and exception trapping in a multithreaded computer system. In particular, the techniques include synchronization support for a thread blocked in a word, demand evalution of values, parallel access of multiple threads to a list, synchronized and unsynchronized access to a data buffer, use of fowarding to avoid checking for an end of a buffer, use of sentinel work to detect access past a data structure, concurrent access to a word of memory using different synchronization access modes, and use of trapping to detect access to restricted memory.

Abstract: In one embodiment, a method for controlling reads in a computer input/output (I/O) interconnect is provided. A read request is received over the computer I/O interconnect from a first device, the request requesting data of a first size. Then it is determined whether fulfilling the read request would cause the total size of a completion queue to exceed a first predefined threshold.

Abstract: A design structure embodied in a machine readable storage medium for designing, manufacturing, and/or testing a design is provided. The design structure generally includes a computer system that includes a CPU, a memory controller, memory, a bus connecting the CPU, memory controller and memory, circuitry for providing a speculative read threshold corresponding to a selected percentage of the total number of reads that can be speculatively issued, and circuitry for intermixing demand reads and speculative reads in accordance with the speculative read threshold.

Abstract: Data packet buffering system comprising a data buffer for buffering data packets, a first counter (24) preloaded with the data packet size (32) and decremented at each read clock signal of a number of logical units corresponding to the width of the output bus (18), a second counter (28) preloaded with the data packet size and decremented at each write clock signal of a number of logical units corresponding to the width of the input bus (14), the decrementation of the second counter being started at the same time as the decrementation of the first counter by a start counter signal (38), and a threshold unit (52) for determining the minimum threshold from the contents of the second counter when the first counter has reached zero and providing the minimum threshold to a buffer management logic unit a buffer management logic unit (22) providing write grant signals when data may be read from the data buffer and sent to an output device.

Abstract: A disk control device stores write requests from a cache memory or reads commands from a host in a queue for a disk drive in chronological order. When the number of write requests stored in the queue for the disk drive is greater than a predetermined value, the storage location of write requests is changed to a queue for an extra disk drive, and the write requests are stored in the queue for the extra disk drive. When the number of write requests stored in the queue for the disk drive becomes smaller than a predetermined threshold, the write requests stored in the extra disk drive are written back to the disk drive.