49 lines
960 B
Text
49 lines
960 B
Text
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.SH
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Sync Copy and WORM Copy Processes
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.PP
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The
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.CW scp
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process
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wakes up every ten seconds and
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issues writes to blocks in the buffer cache
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that have been modified.
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This is done automatically on important
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console commands such as
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.CW halt
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and
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.CW dump .
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.PP
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The
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.CW wcp
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process also wakes up every ten seconds
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and tries to copy a
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.CW dump
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block from the cache to the WORM.
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As long as there are
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.CW dump
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blocks to copy and there is no competition for
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the WORM device,
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the copy will continue at full speed.
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Whenever there is competition for the WORM
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or there are no more blocks to
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copy,
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then the process will sleep ten seconds
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before looking again.
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.PP
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The HP WORM jukebox consists of
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238 disks divided into 476 sides
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or platters.
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Platter 0 is the
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.I A
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side of disk 0.
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Platter 1 is the
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.I A
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side of the disk 1.
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Platter 238 is the
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.I B
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side of disk 0.
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On Emelie,
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the main file system is configured
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on both sides of the first 237 disks,
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platters 0\-236 and 238\-474.
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