Storage system providing file aware caching and file aware remote copy

• US 7,069,393 B2
• Filed: 10/16/2002
• Issued: 06/27/2006
• Est. Priority Date: 06/03/2002
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Sonoda, Koji, Kitamura, Manabu, Matsunami, Naoto, Miyata, Kenichi
• Primary Examiner(s): Padmanabhan, Mano
• Assistant Examiner(s): Doan, Duc T
• Application Number:
  US10/270,514
• Publication Number:
  US 20030225972A1
• Time in Patent Office: 1,350 Days
• Field of Search: 711/112, 711/113, 711/114
• US Class Current: 711/145
• CPC Class Codes: G06F 12/0866 for peripheral storage systems, e.g. disk cache
• CPC Class Codes: G06F 12/0888 using selective caching, e.g. bypass
• CPC Class Codes: G06F 12/126 with special data handling, e.g. priority of data or instructions, handling errors or pinning
• CPC Class Codes: Y10S 707/99931 Database or file accessing

Abstract

A computer system in which a host computer is connected to a storage unit, the storage unit operating in a unit of a file. A file attribute control unit and the storage unit execute the processing being linked together so that, in response to a request from a client computer, the host computer executes a file attribute control program to add a particular attribute to the file, and that the storage unit operates in response to the attribute that is added.

Claims

1. A system for storing files comprising:

a host computer coupled to a plurality of client computers, each client computer sending a file access request which has a staging and de-staging request; and

a first storage unit coupled to the host computer, wherein

the first storage unit has a first disk device, a first cache memory and a first disk controller coupled to the first disk device and the first cache memory, the first disk controller receiving block data sent from the host computer and storing the block data in the first cache memory and controlling to stage or de-stage for each block data and

the host computer has an operating system, which configures a file system in the first storage unit and manages the correspondence between a file of the file system and a plurality of blocks data in the first disk device configuring the file, and a first control unit,

wherein the first control unit is configured to receive each file access request and send to said first storage unit a plurality of attribute setting/changing instructions which are used to set/change an attribute information of each block data corresponding to each file access request based upon the staging and de-staging request, and

the first disk controller is configured to manage the attribute information for each block data and receive the plurality of attribute setting/changing instructions and setting/changing the attribute information based on the received attribute setting/changing instructions from the first control unit and is configured to recognize the need for staging or destaging based upon the attribute information for each block data and controls staging and destaging based upon such recognition, wherein the staging causes the block data to be transferred to the first cache memory from the disk device, and the destaging causes the block data to no longer have permission to reside in the first cache memory,

whereby block data of the file designated by each client computer is staged or destaged in the first cache memory of the first storage unit, and

whereby the first storage unit stores data blocks in said first disk device corresponding to a plurality of files from the plurality of client computers.

2. A system for storing files according to claim 1 further comprising:

a second storage unit coupled to the first storage unit, the second storage unit having a second disk device and a second disk controller coupled to the second disk device, and

wherein the control unit is configured to receive information indicating a particular file, whose data is duplicated in the first storage unit and the second storage unit, specify blocks configuring the particular file designated in the received information by utilizing the correspondence between the file of the file system and the plurality of blocks data in the disk device of the first storage unit, and instruct the first storage unit to duplicate data of the specified blocks to the second disk device of the second storage unit, and

the first disk controller of the first storage unit is configured to send the data of the blocks specified by the control unit to the second storage unit and the second storage unit is configured to store the received data in the second disk device of the second storage unit according to an instruction from the control unit, whereby

data configuring the particular file is duplicated in the first storage unit and the second storage unit.

3. A system for storing files according to claim 2, wherein

the control unit is configured to specify blocks storing file data of the file and blocks storing meta data of the file.

4. A system for storing files according to claim 2, wherein

the control unit is configured to receive information indicating a directory including at least one file, whose data is duplicated in the first storage unit and the second storage unit, specify blocks configuring the at least one file included in the directory designated in the received information according to the configuration of the file system configured by the operating system, and instruct the first storage unit to duplicate data of the specified blocks to the second disk device of the second storage unit, and

the first disk controller of the first storage unit is configured to send the data of the blocks specified by the control unit to the second storage unit and the second storage unit is configured to store the received data in the second disk device of the second storage unit according to an instruction from the control unit, whereby

data of the at least one file included un the directory is duplicated in the first storage unit and the second storage unit.