Matsushita Electric Industrial Co., Ltd.

Hideo Ishida

Yutaka Tanaka

Teruto Hirota

Akihiko Wada

Kunihiko Sakoda

Toshiyuki Ochiai

Keiji Okamoto

Eiichi Toyonaga

A data transfer system comprises a plurality of terminals; a plurality of high-speed data transfer units connected to the terminals through a network, each data transfer unit comprising a plurality of storage devices and a storage device group control device or unit for controlling readout of data from the storage devices, and dividing and storing data requested by the terminals; a virtual storage device group controlling device or unit for controlling readout of data from virtual storage device groups, each virtual storage device group being constructed by selecting a storage device from each high-speed data transfer unit; and an instruction conversion unit or device for receiving a data readout instruction on the basis of data requests output from the terminals, which instruction is given to the virtual storage device groups, from the virtual storage device group control unit or device, and converting the instruction into a data readout instruction to the storage devices from the storage device group control unit or device. In this data transfer system, the load for the data transfer processing is equally distributed among the high-speed data transfer units even when data transfer requests are output from plural terminals.

Data transfer system which divides data among transfer units having

A memory control device having a plurality of data transfer paths including a storage device group comprising a plurality of storage devices for storing data and a buffer memory group comprising multiple buffer memories for storing transferred data, dividing files into multiple blocks for storing blocks in multiple storage devices on different data transfer paths, and executing control to read data from the storage device to be output with a request from a connected terminal to the buffer memory wherein storage devices on different paths create multiple virtual storage device groups, and buffer memories create virtual buffer memory groups. The memory control device comprises a data output control for executing control in a first cycle, the data being temporarily dividedly stored in a prescribed virtual storage device group. In a second cycle the device outputs data stored in the virtual buffer memory group and by alternately repeating first and second cycles, data read from the plural virtual buffer memories group is switched.

Alternate selection of virtual data buffer pathways

In a data transfer system in which when a first to fourth terminals require reading data, the data are read out of a first to fourth storages to be stored in a first and second buffer memories while a first and second virtual groups of storages are alternately switched every constant cycle, and thereafter a first and second data sending units send the data stored in the first and second buffer memories to the terminals; on the other hand, when the first to fourth terminals require writing data, received data is divided in a way to distribute the process loads of data read and data write of the divided data equally into a first and second data transfer units. At the same time, the data are stored in the first and second buffer memories of the first and second data transfer units, and thereafter the data are written into the first to fourth storages while switching the first and second virtual groups of storages alternately. As a result, the load of transferring data to the terminals is not concentrated on a particular data transfer unit in the data transfer system, even when the rate of request-to-reads from the terminals changes or differs from those of others.

Data transfer system

Growing community of inventors

Katanosi, Japan

Hideo Ishida