Disk Shadowing
نویسندگان
چکیده
Disk shadowing is a technique for maintaining a set of two or more identical disk images on separate disk devices. Its primary purpose is to enhance reliability and availability of secondary storage by providing multiple paths to redundant data. However, shadowing can also boost UO performance. In this paper, we contend that intelligent device scheduling of shadowed disks increases the I/O rate, by allowing parallel reads and by substantially reducing the average seek time for random reads. In particular, we develop an analytic model which shows that the seek time for a random read in a shadow set is a monotonic decreasing function of the number of disks in the set.
منابع مشابه
Tandem TR 88.5 DISK SHADOWING
. ABSTRACT Disk shadowing is a technique for maintaining a set of two or more identical disk images on separate disk devices. Its primary purpose is to enhance reliability and availability of secondary storage by providing multiple paths to redundant data. However, shadowing can also boost I/O performance. In this paper, we contend that intelligent device scheduling of shadowed discs increases ...
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