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#7 Peek ahead with mmap()

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nobody
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5
2002-08-19
2002-08-19
Anonymous
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If I use madplay compiled with mmap-support sometimes
the sound skips when the drive shows some heavy read
activity. This doesn't happen when I give mpg123 a
larger-than-default
buffer e.g. 4MB is sufficient in general. I see with
mmap() the OS
should do the whole buffering for you but this seems to
fail
with many concurrent processes accessing the (cd-rom)
drive Especially if the drive contains some bad areas
(dirt?) and a read access takes longer than average the
buffer strategy will fail. Would it be possible to peek
some bytes ahead (one-peek-per-page) so that the OS is
forced to read the sectors at once? This way the sector
will be pre-buffered. A commandline option for the size
of this ahead-read would be nice.

MichaelCore (at) t-online (dot) de

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