| 摘要 |
A disk input/output (1/O) system includes a controller, a cache, a disk UO subsystem, and a command queue. The load on the queue is monitored and when it reaches a threshold, commands are designated cache only. Cache only commands are added to the queue only if they can be completed without accessing the disk (110) subsystem. If the disk (110) subsystem would be accessed in order to complete a cache only command, the command is returned to the operating system with an error. The operating system can then add the command to an operating system or back-up queue. |
