摘要:
A system and method avoids “livelock” and “starvation” among two or more input/output (I/O) devices of a symmetrical multiprocessor (SMP) computer system competing for the same data. The SMP computer system includes a plurality of interconnected processors, one or more memories that are shared by the processors, and a plurality of I/O bridges to which the I/O devices are coupled. A cache coherency protocol is executed the I/O bridges, which requires the I/O bridges to obtain “exclusive” (not shared) ownership of all data stored by the bridges. In response to a request for data currently stored by an I/O bridge, the bridge first copies at least a portion of that data to a non-coherent buffer before invalidating the data. The bridge then takes the largest amount of the data saved in its non-coherent buffer that its knows to be coherent, and releases only that known coherent amount to the I/O device, and then discards all of the saved data.
摘要:
A system and method avoids “livelock” and “starvation” among two or more input/output (I/O) devices of a symmetrical multiprocessor (SMP) computer system competing for the same data. The SMP computer system includes a plurality of interconnected processors, one or more memories that are shared by the processors, and a plurality of I/O bridges to which the I/O devices are coupled. A cache coherency protocol is executed the I/O bridges, which requires the I/O bridges to obtain “exclusive” (not shared) ownership of all data stored by the bridges. In response to a request for data currently stored by an I/O bridge, the bridge first copies at least a portion of that data to a non-coherent buffer before invalidating the data. The bridge then takes the largest amount of the data saved in its non-coherent buffer that its knows to be coherent, and releases only that known coherent amount to the I/O device, and then discards all of the saved data.
摘要:
A system and method avoids passive release of interrupts in a computer system. The computer system includes a plurality of processors, a plurality of input/output (I/O) devices each capable of issuing interrupts, and an I/O bridge interfacing between the I/O devices and the processors. Interrupts, such as level sensitive interrupts (LSIs), asserted by an I/O device coupled to a specific port of the I/O bridge are sent to a processor for servicing by an interrupt controller, which also sets an interrupt pending flag. Upon dispatching the respective interrupt service routine, the processor generates two ordered messages. The first ordered message is sent to the I/O device that triggered the interrupt, informing it that the interrupt has been serviced. The second ordered message directs the interrupt controller to clear the respective interrupt pending flag. Both messages are sent, in order, to the particular I/O bridge port to which the subject I/O device is coupled. After forwarding the first message to the I/O device, the bridge port forwards the second message to the interrupt controller so that the interrupt can be deasserted before the interrupt pending flag is cleared.
摘要:
A method and apparatus for accommodating the speed requirements of a DMA read request from PCI protocol I/O devices attached via a DMA to a multiprocessor system mesh. A bridge between the device controller and the mesh is described which buffers the data from the memory in cache lines from which the data is delivered finally to the I/O device. The system is adaptive in that the number of cache lines required in past reads are remembered and used to determine if the number of cache lines is reduced or increased.
摘要:
A system and method for controlling a shared memory bus in a computer of a multi-processor system prevents collisions on the shared bus and ensures that the bus is full at system start-up. Steady state operations are maintained without the need for a queuing mechanism in the system's memory controller and in view of the memory modules of the shared memory having different read access times, with the system and method being implemented in a system that includes a central unit and multiple uni-directional buses that are disposed between a shared memory and a plurality of processors, with the central unit controlling access to, and use of, the shared buses of the system.
摘要:
This invention relates to nucleic acid molecules comprising at least one nucleic acid sequence encoding for a peptide or protein of interest, at least one nucleic acid sequence encoding for a selectable marker, and at least one IRES sequence, wherein the at least one IRES sequence is located between the at least one nucleic acid sequence encoding for the peptide or protein of interest and the at least one nucleic acid sequence encoding for the selectable marker. Furthermore, this invention relates to host cells comprising such nucleic acid molecule and to methods of recombinant protein expression using such host cells.
摘要:
A clock mechanism in modules connected to a bus over which asynchronous operations are performed wherein clock pulses are generated that can clock the transmission or capture of data and the transitioning of acknowledge or synchronization lines. Each clock mechanism generates its clock pulses based on the receipt of signals associated with synchronization or acknowledge bus lines. The clock mechanism includes a multiplexer which provides to a resettable latch a signal associated with the condition of the selected line. The resettable latch, in conjunction with a delay element produces the clock pulses.
摘要:
This invention relates to nucleic acid molecules comprising at least one nucleic acid sequence encoding for a peptide or protein of interest, at least one nucleic acid sequence encoding for a selectable marker, and at least one IRES sequence, wherein the at least one IRES sequence is located between the at least one nucleic acid sequence encoding for the peptide or protein of interest and the at least one nucleic acid sequence encoding for the selectable marker. Furthermore, this invention relates to host cells comprising such nucleic acid molecule and to methods of recombinant protein expression using such host cells.
摘要:
A technique provides data from an information signal. The technique involves receiving the information signal in the forwarded clock device synchronously with a forwarded clock signal. The technique further involves recovering data contained within the information signal synchronously with a recovery clock signal such that the data is recovered with (i) a particular cycle latency when the recovery clock signal has an optimal rate for the forwarded clock device, and (ii) a different cycle latency when the recovery clock signal has a sub-optimal rate. The particular cycle latency may include more cycles than the different cycle latency. As such, the time latency may be shorter when the recovery clock signal has the sub-optimal rate.
摘要:
A cochlear implant wherein the return path of the electrode array is located to increase current flow through the modiolus. The return electrode is placed at various locations outside the cochlea, and into the modiolus itself. In addition, the electrode array includes an inflatable membrane that is inflated to anchor the array in position in the cochlea with the electrode contacts pressed into contact with the modiolar wall and allowing the membrane to seal with the surrounding tissue of the cochlea, increasing the longitudinal resistance along the cochlear implant electrode, decreasing shunting of the injected current via scala tympani. In experiments that were conducted the current along the modiolus was determined to be, on average, 2.4 times larger with the return electrode in the modiolus than in an extracochlear location.