Hitachi, Ltd.

Sumihiro Miura

Masanori Fujii

Naoki Moritoki

Tsukasa Nishimura

Kyohei Ide

Yoshinori Okubo

Hiraki Mikami

The present invention provides a storage system capable of preventing data loss when power failure or other failures occur to an external power supply, by determining whether the capacity corresponding to the write data can be saved from a volatile memory to a nonvolatile memory based on a charged capacity of a battery used as an internal power supply and a non-backed-up (not yet backed-up) data capacity from the volatile memory to the nonvolatile memory, when storing data from a host computer or a system drive to the volatile memory of the storage system. If it is determined that saving of data is possible, an area corresponding to the write data capacity is allocated in the volatile memory and data is written to the allocated area, but if it is determined that saving of data is not possible, the writing of data is suppressed.

Storage system and method for controlling the same

A storage control apparatus of the present invention is able to duplicatively manage data in a cache memory even during maintenance work. When a memory package CMPKspecified by a user is removed from the apparatus(S), a microprocessorchanges a pair that has been configured using CMPKand CMPKto a pair of CMPKand a free area of a CMPK. As a result, received data (S) is respectively written to multiple cache memories (S, S), and duplicatively managed.

Storage control apparatus and storage control apparatus memory control method

It is provided a storage system for storing data requested by a host computer to be written, the storage system comprising: at least one processor, a cache memory and a cache controller. The cache memory includes a first memory which can be accessed by way of either access that can specify an access range by a line or access that continuously performs a read and a write. The cache controller includes a second memory which has a higher flexibility than the first memory in specifying an access range. The cache controller determines an address of an access destination upon reception of a request for an access to the cache memory from the at least one processor, and switches a request for an access to a specific address into an access to a corresponding address in the second memory.

Storage system and method of controlling storage system

A storage apparatus and its control method capable of shortening data save time at the time of power shutdown are suggested. The storage apparatus includes a processor for controlling reading/writing user data from/to a disk device(s), and a cache memory for storing user data sent and received between a channel adapter and a the disk adapter and control data used by the processor, wherein the control data is sorted into and stored in the nonvolatile memory or the volatile memory according to its update frequency.

Storage apparatus and its control method

A storage system, which is coupled to a computer, includes a storage device, a controller, a plurality of cache memory units, and a connecting unit. Each of the plurality of cache memory units includes: a cache memory for storing data; an auxiliary storage device for holding a content of data even after shutdown of power; and a cache controller for controlling an input/output of data to/from the cache memory and the auxiliary storage device. The cache controller store data stored in the cache memory, which is divided into a plurality of parts, into a plurality of the auxiliary storage devices included in the plurality of cache memory units.

Storage system and data management method

A storage apparatus sets up part of non-volatile cache memory as a cache-resident area, and in an emergency such as an unexpected power shutdown, backs up dirty data of data cached in volatile memory to an area other than the cache-resident area in the non-volatile cache memory, together with the relevant cache management information. Further, the storage apparatus monitors the amount of the dirty data in the volatile cache memory so that the dirty data cached in the volatile cache memory is reliably contained in a backup area in the non-volatile memory, and when the dirty data amount exceeds a predetermined threshold value, the storage apparatus releases the cache-resident area to serve as the backup area.

Storage apparatus and data management method in the storage apparatus

A disk array subsystem makes a diagnosis of a memory device while maintaining performance of a normal access to the memory device contained in a controller, thus enhancing reliability of the memory data. In the disk array subsystem having a disk drive and a controller, the controller has a cache unit and the cache unit has a memory device and a memory control unit. The memory control unit monitors status of memory access by means of a memory access state monitoring unit, issues a diagnosis request while normal access is not made to the memory device, makes access to the memory device for diagnosis of the memory data, and checks the data read from the memory device by using ECC and detects a data error.

Disk array subsystem

To receive a data input/output request from an information processor and writing data in a hard disk drive in accordance with the data input/output request, a storage array controller is provided with a circuit board having a nonvolatile memory functioning as a cache memory for storing the data to be read from or written in the hard disk drive and a circuit board mounting assembly to which the circuit board is removably mounted and in which the circuit board is provided with a removal information output circuit for outputting the circuit board removal information indicating that the circuit board is removed from the circuit board mounting assembly and a data erase circuit for erasing the data stored in the nonvolatile memory when the circuit board removal information is output from the removal information output circuit.

Growing community of inventors

Odawara, Japan

Sumihiro Miura