Hitachi, Ltd.

Hitachi Software Engineering Company, Ltd.

Yoshitaka Ohfusa

Toshiaki Arai

Hisashi Katada

Yasufumi Yoshizawa

Taketoshi Sakuraba

Katsumi Takeda

Masahiro Kitano

Hiroyuki Okura

Hiroo Miyadera

Hirohumi Nagasuka

Keiichi Sasaki

Katsuya Kohda

Tomonori Miyashita

Masayuki Kami

A file sharing method and system for a multiprocessor system has an auxiliary storage unit that is shared in use by a plurality of processors each adopting virtual storage management. An auxiliary page table for storing on a page-by-page basis addresses of files contained in the auxiliary storage unit is prepared on a main storage provided for each of the processors. In response to a file map request issued by a program, an address of the file stored in said auxiliary storage unit is stored in the auxiliary page file. When the file is not stored in the main storage, a page exception interruption occurs, in response to which the address of the file stored in the auxiliary page table is referenced to for thereby transferring the file to the main storage from the auxiliary storage unit. The file stored in the auxiliary storage unit is transferred in the state undergoing an exclusion control.

File sharing method and system for multiprocessor system

An information processing system comprises: plural processors; a shared memory connected to the plurality of processors for enabling communication between the processors; a unit disposed in the shared memory for storing information for specifying a processor connected thereto; and a unit for checking, when a first processor communicates with a second processor, whether or not the first and second processors are connected to the shared memory for direct access thereto by referring to the information storing means. A method of communication between processors used with a multiprocessor system, comprises the steps of: storing information for specifying a processor connected to the shared memory for direct access thereto in a predetermined register of the shared memory; feeding a communication instruction for instructing a first processor to communicate with a second processor via the shared memory; checking, in response to the communication instruction, whether or not the first and second processors are connected to the shared memory to enable direct access; storing communication information from the first processor in the shared memory, in response to confirmation that the first and second processors are connected to the shared memory; feeding a communication read interruption from the shared memory to the second processor; and reading out, in response to the communication read interruption, the communication information from the shared memory to feed the communication information to the second processor.

Multi-processor system having shared memory for storing the

A virtual storage management method in a multi-processor system in which individual processors share an external storage is shown. Data of the virtual storage is stored in the shared external storage, and a page table for managing the virtual storage of each processor is also stored in the shared external storage. By exclusively controlling an access to that page table, the virtual storage can be managed.

Method of managing a virtual storage for a multi-processor system

An information processing system managing a virtual memory by using a real memory system comprising a single or a plurality of processors which, when a real page allocation request occurs in a processor or task keeping the use priority that the real pages of a group among the divided groups of the real pages of said memory can be used in a priority basis, allocated the real pages belonging to said group for which said processor or task keeps the use priority to said processor or task in a priority basis so as to decrease the cache cancel rate and the mapping fault occurrence rate and to allow for smoothing and high speed access of the main memory.

Memory management system for dispatching only to a selected

In a memory system having a storage device and a key storage keeping key data controlling an access to the storage device, there is disposed a key address translation structure for obtaining an address of an entry of the key storage based on an address of the storage device to which an access request is issued. As a result, when subdividing the storage device according to the key data setting unit, each subdivided area can be assigned with a variable size and a plurality of sizes are enabled to be specified for the key data setting units at the same time.

Memory system

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Yokohama, Japan

Yoshitaka Ohfusa