Fwd: Using block device instead of character device for virtio-serial

[Jobin Raju George <jobin.rv@gmail.com>]

---------- Forwarded message ----------
From: Jobin Raju George <jobin.rv@gmail.com>
Date: Sun, Feb 9, 2014 at 11:39 PM
Subject: Re: Using block device instead of character device for virtio-serial
To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: kvm@vger.kernel.org





On Sun, Feb 9, 2014 at 2:42 PM, Stefan Hajnoczi <stefanha@gmail.com> wrote:
>
> On Thu, Feb 06, 2014 at 12:22:36PM +0530, Jobin Raju George wrote:
> > I am trying to establish a communication mechanism between the guest
> > and its host using virtio-serial. For this I am using the following to
> > boot the VM:
> >
> > qemu-system-x86_64 -m 1024 \
> > -name ubuntu_vm \
> > -hda ubuntu \
> > -device virtio-serial \
> > -chardev socket,path=/tmp/virt_socket,server,nowait,id=virt_socket \
> > -device virtconsole,name=v_soc,chardev=virt_socket,name=ubuntu_vm_soc
> >
> > This creates a character device on the guest machine and a UNIX socket
> > on the host machine.
> >
> > 1) Is there a way I can create sockets on the host as well as the guest?
>
> The syntax is documented on the QEMU man page.  Try:
>
> -chardev socket,port=1234,server,nowait,id=virt_socket


I did not try this out, but would this create a "socket" instead of a
character device(/dev/hvc0) on the guest?
>
>
> > 2) Is there a way I can create a block device for communication?
> >
> > I required a block device since the data that is to be transferred is
> > huge and the frequency of the data transfer is quite high.
>
> Have you benchmarked virtio-serial or is this just a guess?


I have not  benchmarked virtio-serial but it seems to be intuitive
that a block device would perform data transfer at a faster rate than
a character device. I may be wrong, would be happy to be corrected.
And yes, I would like to know how can I benchmark virtio-serial using
a character device vs a TCP/IP socket data transfer vs virtio-serial
using a block device.
>
>
> Stefan




-- 

Thanks and regards,

Jobin Raju George

Final Year, Information Technology

College of Engineering Pune

Alternate e-mail: georgejr10.it@coep.ac.in




-- 

Thanks and regards,

Jobin Raju George

Final Year, Information Technology

College of Engineering Pune

Alternate e-mail: georgejr10.it@coep.ac.in