[ofa-general] Re: [PATCH 0/2] Opensm support for external routing engines

[Vincent Ficet]

Hi Sasha,
>> We worked on a scheme that allows to dynamically load external routing 
>> engines.
>>     
>
> Hmm, and why is it really needed? Why to not include routing engine code
> into OpenSM?
>   
The idea is to include non-open source routing algorithms into opensm on
demand, which is permitted by the BSD license.
It also enables to try a new algorithm on the fly without having to
reinstall opensm, which can prove useful on a running cluster.
>> The plugin system is very similar to the perfmgr plugin 
>> implementation.
>>     
> Once it was perfmgr event plugin, now plugin API is generic so what is
> the reason to make yet another plugin interface?
>   
The event-based perfmgr plugin does not make it easy to integrate a new
routing algorithm because the list of available routing algorithms is
statically declared.
>> It allows to provide customised vendor routing engines 
>> and algorithms whithout having to recompile opensm:
>>     
>
> Recompiling OpenSM should not be a big deal. Assuming that it still be
> an open source project.
>   
AFAIK, the latest Voltaire UFM also includes or will include proprietary
routing algorithms (mesh + fat tree), so it could also be useful for
Voltaire.

Cheers,

Vincent