METHOD AND SYSTEM FOR CONTROLLING INPUT/OUTPUT

PURPOSE:To efficiently in parallel execute the right after-processing at every disk device by dividing a slot required for the right after-processing into every disk device, and controlling it. CONSTITUTION:In a controller 2 connected to an input/output device, a cache memory 22 is grouped in accordance with each of the input/output devices and controlled. In such a way, data stored in the input/output device is stored in the cache memory 22 managed in accordance with each of the input/output devices. Subsequently, in response to an input/output request from a host system 1, the data is inputted and outputted to and from the cache memory 22, and thereafter, the data stored in the cache memory 22 is stored in the input/output device. In such a way, by controlling a slot, selecting the slot which is not brought to access from the host system 1 for a long time, and executing a parallel write after-processing at every disk device 23a - 23m, a high performance can be obtained.