On Sat, Oct 15, 2011 at 11:16:04PM +0200, Yaniv Kaul wrote:
> On 10/15/2011 11:05 PM, Dan Kenigsberg wrote:
> > On Sat, Oct 15, 2011 at 10:34:55PM +0200, Yaniv Kaul wrote:
> >> On 10/15/2011 10:19 PM, Dan Kenigsberg wrote:
> >> <SNIP>
> >>> I find it quite awkward for ovirt-engine to send code to MOM. It is not
> >>> like the
> >>> programmers of ovirt-engine are smarter than you and could devise a better
> >>> policy. It *is* important to have "ballooning profiles" attached to
> >>> guests (e.g.
> >>> "this VM is holy, do not balloon unless host is in deep manure") or hosts
> >>> ("keep
> >>> 100Mb free at all costs"). I think that defining the available profiles
> >>> is the
> >>> business of MOM - no one can do it better.
> >>> Dan.
> >> I disagree, for one reason - the engine has an overall view of the
> >> system, not just of a single node.
> >> However, I haven't found yet where it can be advantage. I'm sure
> >> there are such cases, though.
> >> The knowledge of an operating system, its properties (to which user
> >> it belongs, its priority, is it related to another VM, ...) probably
> >> has some value.
> > Sure, but these should be a finite set policies and their parameters.
> > Management
> > layer should be provided with useful knobs and handles, not the ability to
> > push
> > generic code.
> > Can you ever envisage ovirt-engine compiling a completely new policy on its
> > own
> > volition? This would require AI capabilities out of its current scope. The
> > Engine may have several policies dumped in its database, and it would have
> > to
> > apply one of them to a host every time it changes to Up. The only advantage
> > I
> > see in this is that introducing a new policy in a new Engine version is
> > simpler,
> > and does not require updating all of its nodes.
> > Dan.
> Unless the customers want to write their own policies.
Yes, and beyond customers think about vendors. MOM as designed allows for
additional Collectors and Controllers to be dropped in and used by new policies.
Imagine adding a storage appliance that comes with a recommended policy
Adam Litke <a...@us.ibm.com>
IBM Linux Technology Center
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