On Mon, Apr 11, 2011 at 2:33 PM, Tim Serong <tser...@novell.com> wrote: >> >> > For members within a set (sequential=true), it is true that for a given >> >> > member to be active, the previous members must also be active. >> >> > >> >> > Between sets however, it's the other way around - a given set depends on >> >> > the subsequent set. >> >> >> >> Did I really write it like that? You tested it? >> > >> > Yup. Well, I tested it (pcmk 1.1.5), so I assume you wrote it like that :) >> > >> > We want (pardon the ASCII art): >> > >> > /--> C --\ >> > G --> F --+---> D ---+--> B --> A >> > \- -> E --/ >> > >> > Test is: >> > >> > # crm configure colocation c inf: F G ( C D E ) A B >> >> Given the well discussed issues with the shell syntax, I'd prefer to >> see the raw xml actually. > > <constraints> > <rsc_colocation id="c" score="INFINITY"> > <resource_set id="c-0"> > <resource_ref id="F"/> > <resource_ref id="G"/> > </resource_set> > <resource_set id="c-1" sequential="false"> > <resource_ref id="C"/> > <resource_ref id="D"/> > <resource_ref id="E"/> > </resource_set> > <resource_set id="c-2"> > <resource_ref id="A"/> > <resource_ref id="B"/> > </resource_set> > </rsc_colocation> > </constraints>
So, at least for colocation, it looks like we want either the order within the set to be the reverse of what it is now. Ie. <resource_set id="c-2"> <resource_ref id="B"/> <resource_ref id="A"/> </resource_set> Or the order of the sets reversed (so as to work like groups). Ie. <resource_set id="c-2"> <resource_ref id="A"/> <resource_ref id="B"/> </resource_set> <resource_set id="c-1" sequential="false"> <resource_ref id="C"/> <resource_ref id="D"/> <resource_ref id="E"/> </resource_set> <resource_set id="c-0"> <resource_ref id="F"/> <resource_ref id="G"/> </resource_set> Which do people think is going to be more comprehendible? Since we want new behavior, we should use a new syntax to be able to distinguish between the two. Which is handy because the existing syntax is clearly challenging. At a minimum we want s/resource_set/colocation_set/g Two additional open questions, How to indicate the scores: - between the sets Keep using the score from the constraint? - between resources within a set (sequential is clearly too confusing). Perhaps with internal_score and external_score attributes for colocation_set's. Where the value of external_score on colocation_set N reflects the colocation preference with set N-1 (ie. the one above it in xml syntax). And also: - how to deal with roles and instances sanely? In pseudo DTD syntax, I think we're looking at something like: colocation_set ::= id, resource_ref+, internal_score? resource_ref ::= id-ref, action?, role?, instance? With the whole between sets thing to be still worked out. >> > # crm resource stop F >> > (stops F and G) >> > # crm resource start F >> > # crm resource stop D >> > (stops D, F and G) >> > # crm resource start D >> > # crm resource stop B >> > (stops everything except A) >> > >> > That shell colocation constraint maps exactly to the (new) XML shown below >> > (verified just in case it turned out to be a shell oddity). >> > >> >> If so, thats just retarded and needs an overhaul. >> > >> > It is a little... confusing. >> > >> > Regards, >> > >> > Tim >> > >> >> > >> >> > The example colocation chain in Pacemaker Explained right now should >> >> > thus >> >> > be changed as follows in order to match the diagram: >> >> > >> >> > <constraints> >> >> > <rsc_colocation id="coloc-1" score="INFINITY" > >> >> > <resource_set id="collocated-set-1" sequential="true"> >> >> > - <resource_ref id="A"/> >> >> > - <resource_ref id="B"/> >> >> > + <resource_ref id="F"/> >> >> > + <resource_ref id="G"/> >> >> > </resource_set> >> >> > <resource_set id="collocated-set-2" sequential="false"> >> >> > <resource_ref id="C"/> >> >> > <resource_ref id="D"/> >> >> > <resource_ref id="E"/> >> >> > </resource_set> >> >> > <resource_set id="collocated-set-2" sequential="true" >> >> > role="Master"> >> >> > - <resource_ref id="F"/> >> >> > - <resource_ref id="G"/> >> >> > + <resource_ref id="A"/> >> >> > + <resource_ref id="B"/> >> >> > </resource_set> >> >> > </rsc_colocation> >> >> > </constraints> >> >> > >> >> > Regards, >> >> > >> >> > Tim >> >> > >> >> > >> >> > -- >> >> > Tim Serong <tser...@novell.com> >> >> > Senior Clustering Engineer, OPS Engineering, Novell Inc. >> >> > >> >> > >> >> > >> >> > >> >> > _______________________________________________ >> >> > Pacemaker mailing list: Pacemaker@oss.clusterlabs.org >> >> > http://oss.clusterlabs.org/mailman/listinfo/pacemaker >> >> > >> >> > Project Home: http://www.clusterlabs.org >> >> > Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf >> >> > Bugs: >> >> http://developerbugs.linux-foundation.org/enter_bug.cgi?product=Pacemaker >> >> > >> >> >> > >> > >> > >> > >> > -- >> > Tim Serong <tser...@novell.com> >> > Senior Clustering Engineer, OPS Engineering, Novell Inc. >> > >> > >> > >> > _______________________________________________ >> > Pacemaker mailing list: Pacemaker@oss.clusterlabs.org >> > http://oss.clusterlabs.org/mailman/listinfo/pacemaker >> > >> > Project Home: http://www.clusterlabs.org >> > Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf >> > Bugs: >> http://developerbugs.linux-foundation.org/enter_bug.cgi?product=Pacemaker >> > >> > > > > > -- > Tim Serong <tser...@novell.com> > Senior Clustering Engineer, OPS Engineering, Novell Inc. > > > > _______________________________________________ > Pacemaker mailing list: Pacemaker@oss.clusterlabs.org > http://oss.clusterlabs.org/mailman/listinfo/pacemaker > > Project Home: http://www.clusterlabs.org > Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf > Bugs: > http://developerbugs.linux-foundation.org/enter_bug.cgi?product=Pacemaker > _______________________________________________ Pacemaker mailing list: Pacemaker@oss.clusterlabs.org http://oss.clusterlabs.org/mailman/listinfo/pacemaker Project Home: http://www.clusterlabs.org Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf Bugs: http://developerbugs.linux-foundation.org/enter_bug.cgi?product=Pacemaker
