Re: [Qemu-devel] Data classification in Qemu

[Wu Libin]

Cool, the document should be the design of the patch.
The patch is a lustre in intel.
Thanks,-:)

On 17 Sep, 2014, at 5:01 pm, Stefan Hajnoczi <address@hidden> wrote:

> On Tue, Sep 16, 2014 at 11:03:04PM +0800, Wu Libin wrote:
>> Yeah, i know dm-cache, it’s in the layer of block.
>> 
>> Maybe my description is not clear enough.Just because i see a patch, it will 
>> set flags which can classify IO size in bio->bi_flags, and in the function 
>> sd_prep_fn, it will set the SCSI command depends on the bio->bi_flags, like:
>> SCpnt->cmnd[6] = DSS_BIO_CLASS(SCpnt->request->bio);
>> 
>> And i see the data classification function will be enabled when the device 
>> model is “QEMU”, so i guess the QEMU must can recognise the SCSI command. 
>> That’s why i will search the data classification about the QEMU.
>> 
>> It’s true QEMU not care about the filesystem, but we have flags, right, -:).
> 
> After a web search I guess you are are talking about this paper:
> http://sigops.org/sosp/sosp11/current/2011-Cascais/printable/05-mesnier.pdf
> 
> The code isn't upstream and I've never heard of it.
> 
> I think you should get in touch with the authors instead.
> 
> Stefan