Patent ID: 7565508

Claim:
A storage system comprising: a first disk device; a first control device coupled with the first disk device for controlling the first disk device so as to store data, the first control device including at least a first cache memory; a second disk device a second control device coupled with the second disk device for controlling the second disk device so as to store data, the second control device including at least a second cache memory; and a manager device coupled with both the first control device and the second control device through a path; wherein: the manager device is configured to receive a first request for determining a first capacity to be assigned to a first logical partition, and to receive a second request for determining a second capacity to be assigned to a second logical partition; the amount of the first capacity is arranged to be smaller than the capacity of the first cache memory; the manager device is configured to perform processing in order to assign the first capacity in accordance with an amount of the first cache memory to the first logical partition; the manager device is configured to store an amount of capacity as a remaining capacity capable of being assigned to the second logical partition after completion of assignment of the first capacity to the first logical partition; the manager device is configured to perform processing in order to assign the second capacity in accordance with an amount of the second cache memory to the second logical partition, the second capacity determined in response to the second request, if the amount of capacity determined in response to the second request is larger than the remaining capacity and is smaller than the amount of capacity of the second cache memory; and the manager device is configured to perform processing in order to assign the amount of capacity determined in response to the second request in accordance with amounts of both the first and second cache memories for the second logical partition if the amount of capacity determined in response to the second request is larger than the remaining capacity, larger than the amount of capacity of the second cache memory, and smaller than the sum of the remaining capacity and the amount of capacity of the second cache memory.