Re: [Qemu-devel] enabling bus-master IDE driver

[Juergen Lock]

On Tue, Nov 23, 2004 at 04:03:39PM +0000, Norikatsu Shigemura wrote:
> On Tue, 16 Nov 2004 20:41:35 +0100
> Juergen Lock <address@hidden> wrote:
> > > > It now says "Current Transfer Mode: Multi-Word DMA Mode 2".
> > > > I'm not real sure how I test to see if disk access is faster,
> > > > or by how much, but this appears to be progress for XP.
> > > Windows 2000 isn't that verbose - it simply prints "DMA mode".
> > > Interesting that XP has enabled "Multi-Word DMA Mode 2".
> > >...
> > FreeBSD guests (at least 5.3-BETA1) say they use WDMA2, which i guess
> > is the same:
> 
>       Your patch works quite good.  I confirmed that it works on
>       Windows XP SP2 and FreeBSD 5.3-RELEASE as guest OSs, and
>       host's cpu loadavg reduced(MAX: 97% -> 30% on boot, etc..).
> 
> # http://people.FreeBSD.org/~nork/qemu/qemu05.png  but Japanese
> 
>       May I commit your patch as ports/emulators/qemu/files/patch-hw::ide.c?
> 
Mmmh actually I was waiting for words from people in the know about
this, like is WDMA2 really the best we're gonna get?  Since linux guests'
DMA was reported to be faster without the patch...

        Juergen