On Tue, Nov 19, 2013 at 10:38 AM, Spyros Trigazis <[email protected]>wrote:
> > Στις 19 Νοε 2013, 10:49 π.μ., ο/η Michele Tartara <[email protected]> > έγραψε: > > > On Tue, Nov 19, 2013 at 9:37 AM, Helga Velroyen <[email protected]> > wrote: > >> > >> > >> > >> On Tue, Nov 19, 2013 at 9:28 AM, Spyros Trigazis <[email protected]> > wrote: > >>> > >>> > >>> Στις 19 Νοε 2013, 9:55 π.μ., ο/η Helga Velroyen <[email protected]> > >>> έγραψε: > >>> > >>> Hi! > >>> > >>> some thoughts: > >>> > >>> On Fri, Nov 15, 2013 at 8:02 PM, Spyros Trigazis <[email protected]> > >>> wrote: > >>>> > >>>> Hello team, > >>>> > >>>> I'm working on how to pass parameters to the iallocator. Currently the > >>>> default iallocator doesn't accept any parameters from the user. To add > >>>> this functionality a new field named "default_iallocator_parameters" > (or > >>>> something shorter) is going to be added to config.data under cluster. > >>>> Since --mond and --ignore-dynu are both opt-in options the field will > be > >>>> empty by default and the user could modify it calling gnt-cluster > >>>> modify. > >>>> > >>>> Two questions (with obvious answers): > >>>> * The new field in the rpc defs should be a string? > >>> > >>> > >>> Can you give some examples for those parameters? > >>> > >>> > >>> --mond and --ignore-dynu are the only one and it doesn't make sense to > >>> use them combined at the moment since hail queries only the CPU load > >>> data collector. But in the future such need might occur. > >> > >> > >> I see, I would also leave it open for other allocators to be used, but > let's > >> see what michele says about it. > > > > Yes, the idea of accepting any parameter and just "passing it along" > > came up exactly as a way to allow other allocators to be used, given > > that we cannot know what parameters they have. > > This means that ganeti is agnostic to the parameters of any allocator. > > > > > > >> > >>> > >>> > >>> I would imagine them being a string when called on the commandline, > >>> similar to the disk specifications, something like > >>> > >>> --default-iallocator-parameters=key1=value2,key2=value2... > >>> (make the separators consistent, I am not sure they are right in this > >>> example) > >>> > >>> Once the parameters reach RPC level, I would expect them to be in a > >>> dictionary already (similar to hvparams then) > >>> > >>> > >>> ack > > > > Yes, I agree to. Transform the string into a dictionary and then pass > > that along. > > I'm a bit confused. When using a data structure like dictionary means > that we are going to handle the contents of it in some way, check if > something is missing, sorting etc. In our case we are simply passing > them to the next method. Another problem with the dict is the following: > > --mond is a parameter that does take any values. It indicates to query > or not MonD (True/False) but it isn't something like --mond=yes or > --mond=true. So, what is going to be the key value pair? Say, mond: > true. But, another parameter might be --aparameter=2.5. In this case the > key, value pair in the dict is going to be aparameter: 2.5. Finally, > ganeti should know handle them. What do you think? > I agree, binary parameters like --mond should be transformed to yes/no in the dict and the other parameters just get their actual value. This way, of course you need to add a little more transforming logic to ganeti, but still, Ganeti does not need to know much more about the parameters. > > > >>> > >>> > >>> Btw. shouldn't it be only "default_allocator_parameters" (without the > >>> "i"?) since other (hypothetical) allocator implementations could uke > sense, > >>> but maybe give first some examples what the parameters are that you > have in > >>> mind? We se them, too? > >>> > >>> > >>> ack > > > > I think default_iallocator_parameters is the correct name. The generic > > name, the name of the interface, is iallocator > > (http://docs.ganeti.org/ganeti/master/html/iallocator.html), whereas > > the name of our iallocator is hail. > > ack > > > > >>> > >>> > >>>> > >>>> * gnt-cluster info must return the new field, too? > >>> > >>> > >>> I would suggest that, yes. > >>> > >>> > >>> ack > >>> > >>> > >>>> > >>>> > >>>> And two more: > >>>> * What kind of tests should I right? > >>> > >>> > >>> Check that setting and changing and resetting (if reasonable) of the > >>> parameter is done correctly (compare to vgname for example). Add tests > to > >>> iallocator_unittest.py that check if the parameters are read and > processed > >>> correctly. There might be even more chances to test this, those are > just the > >>> ones that come in to my mind directly. > >>> > >>> > >>> ack > >>> > >>> > >>>> > >>>> * Should the user pass parameters to iallocator when invoking > >>>> gnt-instanse add, or he should only modify config.data to do that? > >>> > >>> > >>> I think that would make sense, but maybe give first some examples what > the > >>> parameters are that you have in mind? We could also do that later and > first > >>> go with the one in the cluster config. > >>> > >>> > >>> ack > >>> > >>> Thanks, > >>> Spyros > >>> > >> > >> Cheers, > >> Helga > >>> > >>> > >>> Cheers, > >>> Helga > >>> > >>> -- > >>> -- > >>> Helga Velroyen | Software Engineer | [email protected] | > >>> > >>> Google Germany GmbH > >>> Dienerstr. 12 > >>> 80331 München > >>> > >>> Registergericht und -nummer: Hamburg, HRB 86891 > >>> Sitz der Gesellschaft: Hamburg > >>> Geschäftsführer: Graham Law, Christine Elizabeth Flores > >>> > >>> > >> > >> > >> > >> -- > >> -- > >> Helga Velroyen | Software Engineer | [email protected] | > >> > >> Google Germany GmbH > >> Dienerstr. 12 > >> 80331 München > >> > >> Registergericht und -nummer: Hamburg, HRB 86891 > >> Sitz der Gesellschaft: Hamburg > >> Geschäftsführer: Graham Law, Christine Elizabeth Flores > > > > Thanks, > > Michele > > Thanks, > Spyros > > > > > -- > > Google Germany GmbH > > Dienerstr. 12 > > 80331 München > > > > Registergericht und -nummer: Hamburg, HRB 86891 > > Sitz der Gesellschaft: Hamburg > > Geschäftsführer: Graham Law, Christine Elizabeth Flores > > -- -- Helga Velroyen | Software Engineer | [email protected] | Google Germany GmbH Dienerstr. 12 80331 München Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg Geschäftsführer: Graham Law, Christine Elizabeth Flores
