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Re: Growisofs input cache --> Patch



Joerg Schilling wrote:
Bill Davidsen <davidsen@tmr.com> wrote:

In Run 1 there were several buffer underruns which slowed the DVD recorders down. In Run 2 the buffer was always at 100% (except for the end of course) :-).
This seems reasonable, what were the performance numbers for the other system activity? I'm surprised at the underruns, cdrecord has internal fifo, and I thought you did, too. With a hacked cdrecord (around a50) the burn ran almost eight seconds slower, regardless of burn size, and never dropped below 92% full at the drive, and 70% or so in the fifo.

Hacked how?

Late reply... hacked to use O_DIRECT and some simple monitoring of data count, etc. Clearly writing data with O_DIRECT can be 3-5% slower than using system buffers, but the performance of the other applications was better, no video pauses, all response felt good, generally a better overall behavior.

--
Bill Davidsen <davidsen@tmr.com>
 "Woe unto the statesman who makes war without a reason that will still
be valid when the war is over..." Otto von Bismark


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