Patent ID: 7958259

Claim:
A storage controller which is connected to a plurality of clients for sending a plurality of packets, each of the packets including priority level information designated by the respective clients requesting file access, and a storage device for storing block data configuring a file, and which converts a file access request which is configured from one or more packets sent from the respective clients, to a block access request and sends the block access request to the storage device according to the priority level information included in the one or more packets, the storage controller comprising: a processor controlling the storage controller; and memory storing priority level management information and importance level management information, the priority level management information manages an amount of first data sent by a first client with packets including a first type of priority level and an amount of second data sent by the first client with packets including a second type of priority level which is different from the first type of priority level, the importance level management information manages a total amount of third data sent by the first client as packets requesting file access to a first file managed as a file of a first type of importance level and a total amount of fourth data sent by the first client as packets requesting file access to a second file managed as a file of a second type of importance level which is different from the first type of importance level, the first type of importance level corresponding to the first type of priority level and predetermined by an administrator for the first file, the second type of importance level corresponding to the second type of priority level and predetermined by an administrator for the second file, wherein the processor is configured to: update, upon receiving a packet sent by the first client including the first type of priority level, the amount of the first data managed in the priority level management information, on the basis of an amount of data included in the received packet; update, upon receiving a packet sent by the first client configuring file access to the first file, the total amount of the third data managed in the importance level management information on the basis of an amount of data included in the received packet; determine whether the first client is appropriate or inappropriate based on a comparison of the amount of the first data and the total amount of the third data; use, if the first client is appropriate according to the determination, a first set of a plurality of paths to send the block access requests, corresponding to the packets sent from the first client, to the storage device; and use, if the first client is inappropriate according to the determination, a second set of the plurality of paths to send the block access requests to the storage device.