Patent ID: 8863145

Claim:
A storage system comprising: a plurality of disk devices configured to store data; and a controller including a plurality of channel adapters, each of the plurality of channel adapters comprising one or more interfaces for receiving a request from a host computer and a plurality of processors for processing the request from the host computer, each of the plurality of processors of the plurality channel adapters configured to: process a processing relevant to the request; distribute the processing to another processor of the plurality of processors of the plurality channel adapters; determine whether or not to distribute the processing in accordance with a ratio between a number of the processing processed by an own processor and a number of the processing that is distributed by the own processor to said another processor and processed by said another processor; receive a notification that the processing is finished from said another processor if the process is distributed to said another processor; and notify the host computer that the processing is finished, wherein the each of the plurality of processors of the plurality channel adapters is further configured to: manage an average response time of the own processor and an average response time of other processors of the plurality of processors; determine the ratio according to whether or not a current entire average response time of the own processor and the other processors is shorter than a previous entire average response time; when the current entire average response time is shorter than the previous entire average response time, increase a number of distributing the processing to the other processors of the plurality of processors; when the current entire average response time is longer than the previous entire average response time, reduce the number of distributing the processing to the other processors of the plurality of processors, and wherein an entire average response time is calculated based on a regular write average external response time, a remote copy write average external response time, and an average external response time of the other processors.