Linus Torvalds wrote:
Although it porbably does mean that the problem tends to be more in the really bad mode0 case (600ns -> 150us/sector -> milliseconds for multi-sector transfers).
.. Heh.. it's worse that that: even with commonplace mode4 (120ns) transfers, each PCI bus transaction from start to finish often takes about 1us, so for a 16-sector multi-sector read, that means 4ms+ with interrupts off.
I forget what our multi-sector limit is, I think it tends to be 16. So you'll never get _really_ long irq-off times, but "several ms" is still pretty damn bad.
.. It's a device limit, usually 8 or 16 sectors for nearly all drives now. Cheers -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
