On Thu, Jun 16, 2011 at 03:52:37PM -0600, Alan Robertson wrote: > On 06/16/2011 02:51 AM, Lars Ellenberg wrote: > > On Thu, Jun 16, 2011 at 09:48:20AM +0200, Florian Haas wrote: > >> On 2011-06-16 09:03, Lars Ellenberg wrote: > >>> With the current "unique=true/false", you cannot express that. > >> Thanks. You learn something every day. :) > > Sorry that I left off the "As you are well aware of," > > introductionary phrase. ;-) > > > > I just summarized the "problem": > > > >>> Depending on what we chose the meaning to be, > >>> parameters marked "unique=true" would be required to > >>> either be all _independently_ unique, > >>> or be unique as a tuple. > > And made a suggestion how to solve it: > > > >>> If we want to be able to express both, we need a different markup. > >>> > >>> Of course, we can move the markup out of the parameter description, > >>> into an additional markup, that spells them out, > >>> like<unique params="foo,bar" /><unique params="bla" />. > >>> > >>> But using unique=0 as the current non-unique meaning, then > >>> unique=<small-integer-or-even-named-label-who-cares>, would > >>> name the scope for this uniqueness requirement, > >>> where parameters marked with the same such label > >>> would form a unique tuple. > >>> Enables us to mark multiple tuples, and individual parameters, > >>> at the same time. > > If we really think it _is_ a problem. > If one wanted to, one could say > unique=1,3 > or > unique=1 > unique=3 > > Then parameters which share the same uniqueness list are part of the > same uniqueness grouping. Since RAs today normally say unique=1, if one > excluded the unique group 0 from being unique, then this could be done > in a completely upwards-compatible way for nearly all resources.
That is what I suggested, yes. Where unique=0 is basically "not mentioning the unique hint". -- : Lars Ellenberg : LINBIT | Your Way to High Availability : DRBD/HA support and consulting http://www.linbit.com _______________________________________________________ Linux-HA-Dev: [email protected] http://lists.linux-ha.org/mailman/listinfo/linux-ha-dev Home Page: http://linux-ha.org/
