On 10/05/2016 10:43 AM, Nikolay Shirokovskiy wrote: > adding cc > > On 26.09.2016 13:36, Nikolay Shirokovskiy wrote: >> >> On 26.09.2016 13:04, Peter Krempa wrote: >>> On Mon, Sep 26, 2016 at 12:15:42 +0300, Nikolay Shirokovskiy wrote: >>>> On 26.09.2016 12:01, Peter Krempa wrote: >>> [...] >>> >>>> Sorry, I forget to write down the motivation. >>>> >>>> Internally qemu uses 3 orthogonal flags to configure disk cache. They >>>> are exposed in interface too quite long time ago (29c4e2b). All-in-one >>>> cache parameter that libvirt uses now do not provide all possible >>>> values (5 vs 8). For example absent combination of direct + no flush (no sync) >>>> is useful to speed up tests. >>> Well, if there are useful combinations we can add them to the existing >>> cache setting. >>> >>>> So I decided to provide new possibilities just as qemu does - keep >>>> old parameter and use new ones to tune over. >>> I don't think this is a good idea at all. It's very qemu specific and >>> can be mapped to existing elements. >>> >>> Peter >>> >> Well up until now libvirt cache settings are exactly the same as the qemu ones. I thought >> it would be inconsistent to intordocuce new name and then map internallly to >> qemu. Another point is that these 3 parameters are probably not that qemu specific. >> >> Nikolay >> >> -- >> libvir-list mailing list >> libvir-list@xxxxxxxxxx >> https://www.redhat.com/mailman/listinfo/libvir-list >> the problem is that current modes are a little bit adhoc. The describe non-trivial combination of 3 parameters, which could be tuned on/off independently. That is why it would be more clear to use the approach with separate flags. Den -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list