[ofa-general] New proposal for memory management

[Woodruff, Robert J]

Brian wrote,
>In short, while I'd love to see tag matching, I'd rather make sure all the
>other issues get solved properly first.  Otherwise, we've just added another
>interface that drives me up the wall.

Well I agree that the other issues will need to be solved in any case, as 
even if we were able to get tag-matching into all the hardware, the lead 
time for this would be very long, so MPIs are going to have to deal with
using the current verbs for the foreseeable future. 

I am still not sure that having the OFA kernel developers create and manage
a registration cache in the kernel is a good idea. As Alexander pointed out, I am not sure
that a one size fits all memory registration cache can be developed that meets
the needs of all applications. 

Of coarse if memory registration was not so expensive and could simply be done
for each operation without a big performance penalty, then we would not
need caching at all. So another way to fix this is to just fix the hardware so
memory registration can be done in the speed path, but this is unfortunately 
something that will likely not happen either.( 

woody