31 may 2012 if le access is sequenal fetch blocks into

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Unformatted text preview: ng it back to host   depends on density of bytes on disk –  increasing, relaKvely quickly     When the OS uses the disk, it tries to minimize the cost of all of these steps   parKcularly seeks and rotaKon 31 May 2012 Disks and File Systems 12 University of Washington Performance via disk layout     OS may increase file block size in order to reduce seeking OS may seek to co ­locate “related” items in order to reduce seeking   blocks of the same file   data and metadata for a file 31 May 2012 Disks and File Systems 13 University of Washington Performance via caching, pre ­fetching   Keep data or metadata in memory to reduce physical disk access   problem?   31 May 2012 If file access is sequen<al, fetch blocks into memory before requested Disks and File Systems 14 University of Washington Performance via disk scheduling   Seeks are very expensive, so the OS afempts to schedule disk requests that...
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