Re: prioritize PCI traffic ?

[Lee Revell]

On 1/17/07, Hans-Peter Jansen <hpj@xxxxxxxxx> wrote:
> Am Montag, 15. Januar 2007 15:53 schrieb Vaidyanathan Srinivasan:
> >
> > 33Mhz 32-bit PCI bus on typical PC can do around 100MB/sec...
>
> Substract roughly n * 5MB for VIA chipsets, where n is the age (1 <= n <=
> 4), and even more for SIS, ATI..

While developing the latency tracer in the -rt kernel, Ingo and others
discovered that some SATA controllers can produce very bad DMA
starvation at higher speeds.  A latency trace of such an event looks
like the entire system is going in slow motion.  Presumably, vendors
do this to improve benchmark scores.

Try forcing your drives to a lower speed.

Lee
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/