On Wed, Jun 02, 2004 at 04:21:35PM -0600, Glenn English wrote:
> On Wed, 2004-06-02 at 14:12, Gene Heskett wrote:
> 
> > Any current ide drive can do 30+ Mb/sec if left 
> > alone by other tasks, often quite a ways on the + side.
> 
> Is that just a burst out of the cache, or can they read dis-contiguous
> files, seek around to other files, wait for latency, and write all at
> the same time that fast? Or even half that fast? If so, and if Linux and
> Intel's IDE controllers lose another 25% moving bits around, it'd still
> be comfortably faster than the tape drive. I think I may have something
> horribly misconfigured.

On Solaris x86, one thing that terribly degrades IDE disk
performance is if the driver does not use dma but uses pio mode.
There are even reports of diagnostic tools saying the drive is
using dma, but digging deeper determines that pio mode is in use.

I know not how to check or configure the HD driver on linux,
but it might be something to check.

-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
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