摘要:
In an information processing system having a data processing apparatus, a control unit for a cache memory, and a storage unit for storing a record, respectively interconnected together, wherein when the control unit receives from the data processing apparatus a write request for a record to be written and if the record to be written is not being stored in the cache memory, the control unit receives a data to be written in the object record from the data processing apparatus and stores the received data in the cache memory. After notifying the data processing apparatus of a completion of a data write process, the control unit checks if the object record in which the data stored in the cache memory is being stored in the storage unit, if the object record is being stored in the storage unit, the data in the cache memory is written in the storage unit, and if not, the data in the cache memory is not written and such effect is notified to the data processing apparatus.
摘要:
A buffered peripheral system comprises a backup memory and a primary control unit which has a buffer memory for temporarily storing a copy of the contents of a buffer memory which stores data to be written to a peripheral device and a control device for issuing a command necessary to write the block stored in the buffer memory device to the peripheral device. The primary control unit also includes a recording device for recording the block number corresponding to the block which was most recently written to the peripheral device. The blocks of data which have been written to the peripheral device is then deleted from the backup memory to make room for storing further blocks of data. The system further has a backup control unit substantially identical to the primary control unit. Only the primary control unit normally operates to control the writing to the peripheral device. Upon detection of the failure of the buffer memory in the primary control unit, the backup control unit completes the operation of writing to the peripheral device by retrieving the blocks of data to be written to the peripheral device from the backup memory device using the block number information.
摘要:
A set of sorted columns of one table stored in a DB machine are binary-searched by a hardware in synchronism with data transfer when another table is read from a disk unit, to select a row to be joined. Where a key word sequence to be searched is stored in ascending or descending order, determination of a maximum address in an area in which key words smaller than a search key are stored and determination of a maximum address in an area in which the key words smaller than or equal to the search key are stored are parallelly executed to determine the store range in one searching.
摘要:
A transmission apparatus exercises insertion control for inserting a client signal and a stuff byte into a payload area in a frame into which the client signal is to be mapped, and sends the frame after the insertion control. In addition, the transmission apparatus inserts the client signal or the stuff byte in columns of the frame into the payload area except a leading column.
摘要:
An apparatus for mapping multiple lower-speed signal transmission frames to a higher-speed signal transmission frame. The apparatus includes buffers configured to buffer the lower-speed signal transmission frames, determination units configured to determine frequency justification information for the lower-speed signal transmission frames, a barrel shifter configured to receive signals output from the buffers, and a controller configured to control the barrel shifter to map the lower-speed signal transmission frames to the higher-speed signal transmission frame based on external settings for the respective lower-speed signal transmission frames and the frequency justification information determined by the determination units. When the minimum unit of the lower-speed signal transmission frames is a channel, the number of the buffers and the number of the determination units correspond to the maximum number of channels that can be multiplexed in the higher-speed signal transmission frame.
摘要:
A packet transmission apparatus includes a transmission unit dividing input data and transferring segments, which are obtained by adding sequence numbers to the respective pieces of the divided data, a switch unit transferring the segments to one of a plurality of reception units, and a reception unit reconstructing an original input packet from the plurality of segments that arrive from the switch units on the basis of the sequence numbers. The reception unit includes a packet buffer storing segments that arrive from the switch units, a determination unit determining, on the basis of the sequence number, whether the segment stored in the packet buffer is to be discarded; and a discard part reading the segment stored in the packet buffer in an order from the segment having an older sequence number and discarding the segment that is determined to be discarded.
摘要:
A power-ON-clear circuit has a reset period when the power supply stops temporarily (or instantaneously) and then that power supply is restored. The power-ON-clear circuit 30 of a semiconductor integrated circuit 200 comprises: a capacitor C31 of which one end is connected to the external power-supply voltage Vcc1; an N-channel MOS transistor Q31 of which the drain is connected to the other end of the capacitor C31, the source is connected to the ground potential, and the gate is connected to the external power-supply voltage by way of a resistor R31; and an inverter INV31 that is connected to the connecting point between the capacitor C31 and MOS transistor Q31 in a stage connection, and is connected to the power supply between the internal power-supply voltage Vcc2 and the ground potential.
摘要:
A disk storage system has a control unit having a plurality of external ports connectable to a mirrored disk including two disks to which write data is written. When the control unit receives two read requests issued from a processor to the disk unit group, a first read operation is performed to read data requested by the first read request from one of the disks and a second read operation is performed to read data requested by the second read request from the other one of the disks. Also, a first transferring operation is performed to transfer data read by the first read operation to one external port of the control unit and a second transferring operation is performed to transfer data read by the second read operation to another external port of the control unit. Further, the data read by the two read operations is transferred to the processor via the external ports.
摘要:
According to one aspect of the present invention, a booster circuit comprises a charge pump, a voltage supply section reducing a power supply voltage and supplying a voltage to the charge pump through an output metal-oxide-semiconductor (MOS) transistor of an operational amplifier and a drive MOS transistor maximizing a drive capacity of the output MOS transistor of the operational amplifier.
摘要:
When receiving a write request from a processor, a control unit checks the condition of existence (or the presence/absence) in a cache for information necessary for generation of an updated value of a parity record, receives write data and reports the completion of the write request to the processor. In asynchronism with the write request from the processor, the control unit performs a load process for that information among the information necessary for generation of the updated value of the parity record which may be prepared in asynchronism with the write request from the processor and a write after process for the updated value of the parity record.