Information processing apparatus, raid controller card, and a mirroring method

A RAID controller card, comprising:

• a cache memory;
• and
• a controller configured to write data to the same address of a first storage device and a second storage device which are configured to write and read data per page and to erase data per block unit comprising pages,
• wherein the controller is configured to:
• write first data to the first storage device from a first write address to a second write address according to a size of the first data when the controller receives a writing instruction comprising the first write address and the first data;
• write second data having first data to the second storage device from a head of the first data, a size of the second data is equal to n times a page size, where n is an integer greater than or equal to 1;
• write, to the cache memory, third data having a size equal to a difference between the size of the first data and the size of the second data, the size of the third data is smaller than the page size;
• and
• write fifth data to the second storage device when the controller receives a writing instruction comprising from a third write address is adjacent to the second write address the fifth data comprising the third data and at least part of fourth data, and a size of the fifth data is equal to the page size.

A mirroring method of writing data to the same address of a first storage device and a second storage device which are configured to write and read data per page and to erase data per block unit comprising pages, the method comprising:

• writing first data to the first storage device from a first write address to a second write address according to a size of the first data upon receiving a writing instruction comprising the first write address and the first data;
• writing second data having data to the second storage device from a head of the first data, a size of the second data is equal to n times a page size where n is an integer greater than or equal to 1;
• writing, to the cache memory, third data having a size equal to a difference between the size of the first data and the size of the second data, the size of the third data is smaller than the page size;
• and
• writing fifth data to the second storage device upon receiving a writing instruction from a third write address adjacent to the second write address, when the controller receives a writing instruction comprising third write address is adjacent to the second write address and fourth data, fifth data to the second storage device, the fifth data comprising the third data and at least part of fourth data, and a size of the fifth data is equal to the page size.