Dynamic allocation of GASPI segments

[gaspi-forum]

Dynamic allocation of GASPI segments

[krzikalla]

Based on the GPI implementation gaspi_segment_unbind is unnecessary, since gaspi_segment_delete already handles bound and allocated segments differently. This should be made clear in the GASPI spec. At least the first sentence of 7.3.1

The synchronous local blocking procedure gaspi_segment_delete releases the
resources of a previously allocated memory segment.

is misleading. It must be read allocated or bound.

[mrahn]

The the question about segment_register: The allreduce implies GetMemory is called by all members of the group. So all new segments are registered with all remote ranks in the group. This looks valid (even though I don't know about registration with the creating rank). Also the segment_register is not using magic but an established connection, according to the spec. But yes, this implies an active component.

[mrahn]

About the unbind: There is no other way delete could behave. But yes, maybe worth mentioning it. Would you mind compiling the small snippets and change sets into a proposal for the forum?

[krzikalla]

Indeed the idea is to discuss and collect the issues here, turn them into proposals and then close them here.

[krzikalla]

Regarding unbind: delete could also (erroneously) try to deallocate the segment memory.