Should this property be filled in on get of RASD? Or is client expected to follow associations to determine pool from which the allocation occurs? AFAICT, DSP1041 (RAP) is not clear on this. Thanks, Jim
JF> Should this property be filled in on get of RASD? Or is client JF> expected to follow associations to determine pool from which the JF> allocation occurs? AFAICT, DSP1041 (RAP) is not clear on this. You mean on regular RASDs that belong to guests? We do set this property on the template RASDs that come from AllocationCapabilities, but that's because we need to know the pool membership on DefineSystem(). Looking up the pool membership during, say, enum of the regular RASDs is just another latency-inducing step, but I suppose it should be done... -- Dan Smith IBM Linux Technology Center Open Hypervisor Team email: danms@us.ibm.com
Dan Smith wrote:
JF> Should this property be filled in on get of RASD? Or is client JF> expected to follow associations to determine pool from which the JF> allocation occurs? AFAICT, DSP1041 (RAP) is not clear on this.
You mean on regular RASDs that belong to guests?
Yes.
Looking up the pool membership during, say, enum of the regular RASDs is just another latency-inducing step, but I suppose it should be done...
Latency will be induced regardless, either on backend or by client following associations :-(. But is it wise to induce latency on the backend, where all users are affected? Is the latency increase on backend small compared to client following associations? I guess my question should really be directed at SVPC. Client developers assume they can get resource pool from PoolID. Generally I think the CIM model advocates associations to describe such relationships. But RAP is not clear on this. Thanks, Jim
JF> I guess my question should really be directed at SVPC. Client JF> developers assume they can get resource pool from PoolID. JF> Generally I think the CIM model advocates associations to describe JF> such relationships. But RAP is not clear on this. Right, PoolID seems like quite a hack to me, and definitely out of place compared to the rest of SVPC. It helps us a little with the template RASDs but we could get by without it. I don't have a strong feeling about it one way or the other, so I'll let someone who does make the call. -- Dan Smith IBM Linux Technology Center Open Hypervisor Team email: danms@us.ibm.com
Dan Smith wrote:
JF> I guess my question should really be directed at SVPC. Client JF> developers assume they can get resource pool from PoolID. JF> Generally I think the CIM model advocates associations to describe JF> such relationships. But RAP is not clear on this.
Right, PoolID seems like quite a hack to me, and definitely out of place compared to the rest of SVPC. It helps us a little with the template RASDs but we could get by without it.
I don't have a strong feeling about it one way or the other, so I'll let someone who does make the call.
Sorry for the delayed response here.. The use case examples in the SVP show the PoolID set on the RASD instances. However, setting the PoolID attribute appropriately, like you've both mentioned, is basically a re-implementation of the ResourceAllocationFromPool association. It seems like a waste of processing to add it. Jim, you says that client developers assume that this attribute is set. Have you run into any situations where its been needed? -- Kaitlin Rupert IBM Linux Technology Center kaitlin@linux.vnet.ibm.com
Kaitlin Rupert wrote:
The use case examples in the SVP show the PoolID set on the RASD instances. However, setting the PoolID attribute appropriately, like you've both mentioned, is basically a re-implementation of the ResourceAllocationFromPool association. It seems like a waste of processing to add it.
Jim, you says that client developers assume that this attribute is set. Have you run into any situations where its been needed?
No, I simply had client developers ask why the property is not set in RASDs. Understandably, they want to use it instead of invoking more CIM operations. IIRC this property was introduced for the "create" use cases, e.g. AddResourceSettings, where there is no way to describe the relationship via associations. However, once the object exists its relationship to other CIM objects is determined via associations. I don't think RAP is very clear in this regard, hence the questions/confusion. Jim
participants (3)
-
Dan Smith -
Jim Fehlig -
Kaitlin Rupert