| 摘要 |
PURPOSE:To obtain an average block size with a little overhead by forming an equation established between the using ratio of a device, the number of I/O and the average block size and solving it simultaneously with the number of the devices. CONSTITUTION:An I/O number count part 15 intercepts an I/O processing by an input and output control part 13 to count the number of the I/O for every device. When a device using ratio measuring part 17 obtains a control at a prescribed time interval by a timer interruption processing part 16, it examines a device busy for every device 21-1-21-3 by referring to an input and output control table 14 to measure the device using ratio. An equation forming and processing part 18 forms and processes the equation established between the device using ratio, the number of the I/O for every device and the average block size for every device. An average block size estimating processing part 19 solves the formed equation simultaneously with the number of the devices, thereby, a processing for obtaining the average block size of an unknown quantity is carried out. Thereby, a direct measurement or the like for every device is eliminated to reduce the overhead for the measurement. |
