itaps-parallel Mesh Instances

[Tim Tautges]

Jason Kraftcheck wrote:
> Mark Miller wrote:
>> This is consistent with my understanding of what Jason proposed in the way
>> of a multi-plexor also based on my review of the code example he sent.
>>
>> And, doesn't this mean that 'co-existance' cannot be solved by a multiplexor?
>> Or, does it only mean that it cannot be solved by the currently proposed
>> multiplexor?
> 
> Given the current C interface, an entity is uniquely identified by the
> tuple {mesh_instance,entity_handle}.  If the multiplexer where to present
> the fiction of a single mesh_instance combining two real mesh instances,
> it would need some mechanism to determine the mesh_instance from the
> entity_handle.  Given that a specific handle value may identify valid
> entities in both interfaces, it would be necessary for the multiplexer to
> create its own handle space and map from each 'virtual' handle to a real
> handle and mesh_instance.  I'd probably implement this using integer
> handle values, where the highest bits index into an array of
> mesh_instances and the lower bits index into a map to the handle in the
> mesh instance.
> 
> This seems expensive.  Why would anyone want to do this?
> 

In some cases this might be much cheaper than duplicating the data (not 
only the mesh but also the tags/sets) in a 3rd instance and operating on 
it there.

- tim

> - jason
> 
> 
> 

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             Tim Tautges            Argonne National Laboratory
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