6b46c62d2e
File too long (should be no more than 24 lines). Line too long (should be no more than 80 characters). Trailing empty lines. Trailing white-space. Trucated the long files as best as possible while preserving the most info contained in them.
24 lines
1.1 KiB
Text
24 lines
1.1 KiB
Text
This is a program designed to speed up writing tapes on remote tape drives.
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Requirements are shared memory and locks which normally means that these are
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supported in your kernel. [for FreeBSD/NetBSD, this means you MUST have a kernel
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with options SYSVSHM compiled in - markm]
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Buffer has been tested under SunOS 4.0.*, SunOS 4.1.*, Solarix, HP-UX 7.0, and
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Gould UTX 2.1A (sv universe).
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The program splits itself into two processes. The first process reads (and
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reblocks) from stdin into a shared memory buffer. The second writes from the
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shared memory buffer to stdout. Doing it this way means that the writing side
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effectly sits in a tight write loop and doesn't have to wait for input.
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Similarly for the input side. It is this waiting that slows down other
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reblocking processes, like dd.
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I run an archive and need to write large chunks out to tape regularly
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with an ethernet in the way. Using 'buffer' in a command like:
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tar cvf - stuff | rsh somebox "buffer > /dev/rst8"
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is a factor of 5 faster than the best alternative, gnu tar with its
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remote tape option:
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tar cvf somebox:/dev/rst8 stuff
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