Patent ID: 7421538
Filing Date: 2008-09-02
Classification: G06F

Abstract:
1. A storage control apparatus for accessing a storage device according to a data access request from a requesting apparatus, comprising: a first controller which has a first cache memory and is in charge of a first storage device out of a plurality of storage devices; and a second controller which has a second cache memory and is in charge of a second storage device out of said plurality of storage devices, wherein said first controller further comprises a first mirror management table for managing allocation of a storage page in a mirror area of said second cache memory, and said second controller further comprises a second mirror management table for managing allocation of a storage page in a mirror area of said first cache memory, wherein when said first controller receives a data write request containing write data from said requesting apparatus, said first controller allocates a page in a read/write area of said first cache memory, acquires a storage page in the mirror area of said second cache memory by referring to said first mirror management table, writes the write data from said requesting apparatus to the page allocated in the read/write area of said first cache memory, and copies the write data to the acquired page in the mirror area of said second cache memory, and wherein said first and second controllers mutually notify the sizes of said first and second cache memories, allocate the mirror areas of said first and second cache memories according to the sizes of said first and second cache memories, and create said first and second mirror management tables from said allocation.