Sorry I missed "Matt Thomas" reply. I will try raw device.
Thanks

On 3/10/07, Maen Suleiman <maen.suleiman@gmail.com> wrote:
>  What do you think the reason we are seeing maximum of 8KB on
> copyin\out although we are telling dd to use 128KB block size. we are
> reading from SATA disk (SCSI implementation) or USB disk .
>
> Thanks
>
>
> On 3/10/07, Jason Thorpe <thorpej@shagadelic.org> wrote:
> >
> > On Mar 9, 2007, at 2:14 PM, Maen Suleiman wrote:
> >
> > > Hi,
> > >
> > > We are implmenting copyin\out using DMA engine, and we have noticed
> > > that the maximum buffer size is 8KB (for example when using 'dd
> > > if=/dev/sd0c of=/dev/null bs=131072' ) , Is there a reason for this?
> > > can this size be increased ?
> >
> > I don't think there's any inherent limit in copyin/copyout.  Physio is
> > a different story -- it doesn't use copyin/copyout at all.
> >
> > >
> > >
> > > Thanks in advance
> >
> > -- thorpej
> >
> >
>