Storage apparatus and its data processing method

A data processing method for a storage apparatus including:

• a first controller for sending or receiving information to or from one or more access requesters via a network and controlling data input/output processing on a buffer;
• and
• a second controller for sending or receiving data to or from the first controller and controlling data input/output processing on storage devices;
• the data processing method comprising:
• a step executed by the first controller of managing its load by associating it with one or more logical units which are access targets of the access requester in a process of executing the data input/output processing on the buffer;
• a step executed by the first controller, when receiving an access request from the access requester, of judging whether its load exceeds a threshold or not;
• a step executed by the first controller, when it is determined that its load exceeds the threshold, of executing, on the buffer, first data conversion processing for converting data relating to the logical units, which are the access targets of the access requester, from a first block size into a second block size or second data conversion processing for converting the data from the second block size into the first block size;
• a step executed by the first controller, when it is determined that its load does not exceed the threshold, of giving a command to the second controller to execute the first data conversion processing or the second data conversion processing;
• and
• a step executed by the second controller of executing the first data conversion processing or the second data conversion processing based on the command from the first controller.