Re: [Qemu-devel] [PATCH 4/4] qemu-img: conditionally discard target on convert

[Peter Lieven]

Am 18.07.2013 um 16:35 schrieb Paolo Bonzini <address@hidden>:

> Il 18/07/2013 16:32, Peter Lieven ha scritto:
>>>> 
>>> (Mis)alignment and granularity can be handled later.  We can ignore them
>>> for now.  Later, if we decide the best way to support them is a flag,
>>> we'll add it.  Let's not put the cart before the horse.
>>> 
>>> BTW, I expect alignment!=0 to be really, really rare.
>> To explain my concerns:
>> 
>> I know that my target has internal page size of 15MB. I will check what
>> happens
>> if I deallocate this 15MB in chunks of lets say 1MB. If the page gets
>> unprovisioned
>> after the last chunk is unmapped it would be fine :-)
> 
> You're talking of granularity here, not (mis)alignment.

you are right. for the target i am talking about this is 30720 512-byte blocks 
for the granularity (pagesize) and 0 for the alignment.
i will see what happens if I write same w/unmap the whole 30720 blocks in 
smaller blocks ;-) otherwise i will have to add support for honoring this 
values in qemu-img convert
as a follow up.

Peter