Re: [PATCH resend] libxl, hotplug/Linux: default to phy backend for raw format file, take 2

[Fabio Fantoni <fabio.fantoni@m2r.biz>]

Il 09/01/2015 18:38, Dario Faggioli ha scritto:
> On Fri, 2015-01-09 at 14:42 +0000, Wei Liu wrote:
>> On Thu, Jan 08, 2015 at 03:33:17PM +0100, Fabio Fantoni wrote:
>>> Sorry for the probably stupid question, what are the pros and cons of
>>> default use of phy instead qdisk for raw files as domU disk?
>>>
>> There's no stupid question. :-)
>>
>> I was told that it performs better and enables other potential
>> improvements.
>>
> Not a big deal, probably, but IMO it would be nice to have at least a
> few words about when it's happening in the changelog, wouldn't it?

I'm also interested in detailed changelog about.

In the meantime, I saw this:
http://lists.xen.org/archives/html/xen-users/2015-01/msg00047.html
Based on the post above seems that phy will have important risk of data 
loss if I understand good, from Ian Campbell post:
> xl also uses qdisk for raw disk images instead of loop+blkback which
> xend used, because there are concerns that the loop driver can lead to
> data loss (by not implementing direct i/o the underlying device, and/or
> not handling flushes correct, my memory is a bit fuzzy).

Thanks for any reply and sorry for my bad english.


>
> Regards,
> Dario
>