DATA MANAGEMENT APPARATUS, DATA MANAGEMENT METHOD, AND DATA MANAGEMENT PROGRAM

• US 20200133836A1
• Filed: 08/08/2019
• Published: 04/30/2020
• Est. Priority Date: 10/30/2018
• Status: Abandoned Application

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: MIZUSHIMA, Nagamasa, SUGIMOTO, Sadahiro, SHIMADA, Kentaro
• Application Number:
  US16/535,555
• Publication Number:
  US 20200133836A1
• Time in Patent Office: Days
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 12/063 for I/O modules, e.g. memory mapped I/O I/O protocol G06F13/42
• CPC Class Codes: G06F 12/0868 Data transfer between cache memory and other subsystems, e.g. storage devices or host systems
• CPC Class Codes: G06F 12/0871 Allocation or management of cache space
• CPC Class Codes: G06F 12/0873 Mapping of cache memory to specific storage devices or parts thereof
• CPC Class Codes: G06F 2212/1024 Latency reduction
• CPC Class Codes: G06F 2212/312 In storage controller
• CPC Class Codes: G06F 3/0622 in relation to access
• CPC Class Codes: G06F 3/0652 Erasing, e.g. deleting, data cleaning, moving of data to a wastebasket
• CPC Class Codes: G06F 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]

Abstract

A storage system includes: a memory for caching of data according to input and output to a storage device; and a CPU connected to the memory. The memory includes: a DRAM high in access performance; and an SCM identical in a unit of access to the DRAM, the SCM being lower in access performance than the DRAM. The CPU determines whether to perform caching to the DRAM or the SCM, based on the data according to input and output to the storage device, and caches the data into the DRAM or the SCM, based on the determination.

Claims

1. A data management apparatus comprising:

a memory unit for caching of data according to input and output to a storage device; and

a processor unit connected to the memory unit, wherein

the memory unit includes;

a first type of memory high in access performance; and

a second type of memory identical in a unit of access to the first type of memory, the second type of memory being lower in access performance than the first type of memory, and

the processor unit determines whether to perform caching to the first type of memory or the second type of memory, based on the data according to input and output to the storage device, and

caches the data into the first type of memory or the second type of memory, based on the determination.

2. The data management apparatus according to claim 1, wherein

the data according to input and output to the storage device includes:

user data according to an input/output (I/O) command from a host computer; and

management data for management of the user data, and

the processor unit determines to cache the user data into the first type of memory and to cache the management data into the second type of memory.

3. The data management apparatus according to claim 2, wherein

in a case where the first type of memory is not free when the processor unit caches the user data into the first type of memory, the processor unit determines to cache the user data into the second type of memory.

4. The data management apparatus according to claim 2, wherein

in a case where the first type of memory is not free when the processor unit caches the user data into the first type of memory, the processor unit caches the user data into the first type of memory after the processor unit remains on standby until the first type of memory is made free.

5. The data management apparatus according to claim 2, wherein

in a case where the second type of memory is not free when the processor unit caches the management data into the second type of memory, the processor unit determines to cache the management data into the first type of memory.

6. The data management apparatus according to claim 2, wherein

in a case where the second type of memory is not free when the processor unit caches the management data into the second type of memory, the processor unit caches the management data into the second type of memory after the processor unit remains on standby until the second type of memory is made free.

7. The data management apparatus according to claim 2, wherein

the management data includes address data allowing specification of an address for compression and storage of the user data into the storage device.

8. The data management apparatus according to claim 1, wherein

the first type of memory includes a dynamic random access memory (DRAM), and the second type of memory includes a storage class memory (SCM).

9. A data management method with a data management apparatus including a memory unit for caching of data according to input and output to a storage device, the memory unit including a first type of memory high in access performance and a second type of memory identical in a unit of access to the first type of memory, the second type of memory being lower in access performance than the first type of memory, the data management method comprising:

determining whether to perform caching to the first type of memory or the second type of memory, based on the data according to input and output to the storage device; and

storing the data into the first type of memory or the second type of memory, based on the determination.

10. A non-transitory computer-readable storage medium storing a data management program for causing a computer including a data management apparatus including a memory unit for caching of data according to input and output to a storage device and a processor unit connected to the memory unit, the memory unit including a first type of memory high in access performance and a second type of memory identical in a unit of access to the first type of memory, the second type of memory being lower in access performance than the first type of memory,

the data management program causing the computer to function as:

determining whether to perform caching to the first type of memory or the second type of memory, based on the data according to input and output to the storage device; and

storing the data into the first type of memory or the second type of memory, based on the determination.