Messages in this thread | | | Date | Fri, 06 Aug 2004 20:33:52 +0100 | From | Hamie <> | Subject | Re: ide-cs using 100% CPU |
| |
Russell King wrote:
>On Sun, Jul 18, 2004 at 10:30:16AM +0100, Hamie wrote: > > >>Anyone know why this happens? Something busy waiting? (BUt that should >>show as system cpu right?) or something taking out really long locks? >> >> > >It'll be because IDE is using PIO to access the CF card, which could >have long access times (so reading a block of sectors could take some >time _and_ use CPU.) Obviously, PIO requires the use of the CPU, so >the CPU can't be handed off to some other task while this is occuring. > > > Well... I did consider that. And not to disbelieve you, since you know the kernel way better than I do, But decided I was being silly that a 1.6GHz Pentium-M processor should use 100% CPU moving a couple of MB/second across a CF interface...
Is 100% CPU not excessive? IIRC my PIII-750 used to use less CPU doing the same job as quick, or even slightly faster...
And should it not use system CPU rather than user CPU?
TIA Hamish.
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |