Hi,
to be clear, what i mean is, we have four actual physical subclusters, but now only publish them as a single subcluster with for specs, a mix of the average core and lowest-rated core.
I thought the idea behind glue-cluster was to allow publishing (indeed via YAIM and not by-hand hacks) the actual subclusters as glue subclusters. So you are telling me that we could use glite-cluster to publish the single "subcluster" we have now, only once instead of once per CE host that we provide? I guess that use case is useful!
JT
On Feb 22, 2012, at 17:27 , Stephen Burke wrote:
> LHC Computer Grid - Rollout [mailto:[log in to unmask]] said:
>> 2) it is much less than clear to me if EMI CREAM is ready for glite
>> cluster. what i mean is something like this:
>
> One general point is that glite-cluster is purely about yaim configuration, it doesn't do anything you couldn't previously do with configuration by hand and it doesn't change the structure of the information in the bdii or the way that e.g. the WMS interprets it. CREAM as a service (as opposed to a node type) has no interaction at all with glite-cluster.
>
>> c) as far as I know there is no connection -- and here I mean a real,
>> deployed, in production connection, I do not mean a connection like "in
>> theory a site could write its own plugin for BLAH", nor do I mean "you
>> should define a separate queue for each subcluster" -- between CREAM
>> and the batch system that will make sure that torque knows we can only
>> submit to that particular subcluster. so the job most likely goes to a
>> different subcluster and gets killed for exceeding its walltime.
>
> This is a different question, and indeed that is still not supported (Massimo may like to comment on what will happen with glue 2 matching in the WMS). So with or without glite-cluster you still have the restriction of having only one subcluster per cluster, and hence per CE. What glite-cluster does let you do is publish each distinct subcluster only once, instead of once per CE node.
>
>> so unless i want to write BLAH plugins, or multiply the number of CE
>> endpoints we publish (and amount of junk in the BDII) by four (the
>> number of different subclusters we have), we should NOT install and use
>> glite-cluster.
>
> The number of CEs stays the same (unless you choose to change them for other reasons), the change is to reduce the number of Clusters and SubClusters by removing duplicate publication of the same information. And conversely, if you have four subclusters then you should *already* have multiplied the number of CEs by four, i.e. each CE should refer to one and only one subcluster.
>
> Stephen
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