Re: [Qemu-devel] [RFC] Disk integrity in QEMU

[Anthony Liguori]

Avi Kivity wrote:
> I don't think O_DIRECT should be qemu's default, since anyone using qemu
> directly is likely a "causal virtualization" user.  Management systems
> like ovirt should definitely default to O_DIRECT (really, they shouldn't
> even offer caching).
>   

ovirt isn't a good example because the default storage model is iSCSI.  
Since you aren't preserving zero-copy, I doubt that you'll see any 
advantage to using O_DIRECT (I suspect the code paths aren't even 
different).

Regards,

Anthony Liguori