Re: [Qemu-devel] [RFC PATCH 1/1] ceph/rbd block driver for qemu-kvm

[Stefan Hajnoczi]

On Sun, May 23, 2010 at 1:01 PM, Avi Kivity <address@hidden> wrote:
> On 05/21/2010 12:29 AM, Anthony Liguori wrote:
>>
>> I'd be more interested in enabling people to build these types of storage
>> systems without touching qemu.
>>
>> Both sheepdog and ceph ultimately transmit I/O over a socket to a central
>> daemon, right?
>
> That incurs an extra copy.

Besides a shared memory approach, I wonder if the splice() family of
syscalls could be used to send/receive data through a storage daemon
without the daemon looking at or copying the data?

Stefan