METHOD OF REAL-TIME DISK-SCHEDULING, DISK-SCHEDULER, FILE SYSTEM, DATA STORAGE SYSTEM AND COMPUTER PROGRAM PRODUCT

摘要

Disk errors like erroneous sectors, sector re-assignments and erroneous data, usually result in a performance penalty of a data storage disk. Known real-time disk scheduling methods not take into account such performance penalty for scheduling requests and therefore a contemporary scheduler's nominal estimation of the service time of a hard-disk in general is too optimistic. Consequently a contemporary hard-disk may miss its service time restrictions set by the scheduler. The invention proposes disk-scheduling wherein pending requests are arranged to be processed by the disk by taking an estimation of service time of the disk into account under a given condition of a performance behavior of the disk when setting time restrictions for a request. It is proposed, that the estimation is performed on basis of a model, describing the performance behavior of the disk and taking the reduction of the performance of the disk caused by errors into account.