Re: [Qemu-devel] Re: [PATCH] Add cache=volatile parameter to -drive

[Kevin Wolf]

Am 26.05.2010 10:52, schrieb Aurelien Jarno:
> On Tue, May 25, 2010 at 08:31:20PM -0500, Anthony Liguori wrote:
>> On 05/25/2010 04:01 PM, Aurelien Jarno wrote:
>>>
>>> I really think this patch can be useful, in my own case when testing
>>> debian-installer (I already cache=writeback). In short all that is about
>>> developing and testing, as opposed to run a VM in production, can
>>> benefit about that. This was one of the original use case of QEMU before
>>> KVM arrived.
>>>
>>> Unless someone can convince me not to do it, I seriously considering
>>> applying this patch.
>>
>> There really needs to be an indication in the --help output of what
>> the ramifications of this option are, in the very least.  It should
> 
> That's indeed something than can be done, but to avoid double standards,
> it should also be done for other features that can lead to data
> corruption. I am talking for example on the qcow format, which is not
> really supported anymore.

That said, qcow1 is probably in a better state than half of the other
drivers. Basically only raw and qcow2 are really maintained, you'd need
to warn about any other format then.

Kevin