Re: [Qemu-block] virtio-scsi and request splitting

[Peter Lieven]

Am 01.06.2017 um 15:32 schrieb Paolo Bonzini:
> On 01/06/2017 15:30, Peter Lieven wrote:
> > Hi,
> >
> >
> > i noticed a while ago that if I start a job like this in a vserver:
> >
> > dd if=/dev/zero of=/x bs=1M count=128 oflag=direct
> >
> > I see each of the 1M request splitted into 516096 + 516096 + 16384 bytes
> > with virtio-scsi
> >
> > If I use virtio-blk the request goes through with 1M size.
> >
> > Any idea whats the cause of this?
> It may depend on memory fragmentation.

This sounds like nothing that can be influenced or changed?

I forgot to mention, if I specify bs=512k the requests go through also with 
virtio-scsi

Thanks,
Peter