Visual Circuits ReelTime 4, Руководство пользователя

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Appendix
64
The driver will examine the status of the channel buffer data
pointers 200 times a second (this is a parameter, which may be
changed). If the MinDMA is set too small, then there will be a lot
of requests for small amounts of data, which can cause too much
overhead. If the MinDMA is set too big, then a channel may starve
because it may be too close to starving before it can get serviced. If
the MaxDMA is set too small, then system performance will
decrease because of the overhead involved, and if it is set too large,
then other channels may starve because one channel takes too long
to service.
The min and max file read size is also critical for optimizing the
seek time. If the minfileread is set too small, then the disk seek
time will become too great a percentage of the disk access time. If
it is set too high, then the channels will not be serviced often
enough.
These parameter settings have been found to give the best
performance playing multiple high bitrate files off of a single
drive:
BufferSizePerChannel = 0x00400000
minfileread = 0x100000
maxfileread = 0x200000
DSIZEOSD = 0x0000
mindma = 0x10000
maxdma = 0x40000
StarveCheck = 0x0
nocache = 0x1
noreadbuff = 0x1