[openib-general] SA cache design

[Hal Rosenstock]

On Fri, 2006-01-06 at 13:59, Sean Hefty wrote:
> Eitan Zahavi wrote:
> > So if the cache  is on another host - a new kind of MAD will have to be 
> > sent on behalf of
> > the original request?
> 
> I was thinking more in terms of redirection.
> 
> > In IB QoS properties are mainly the PathRecord parameters: SL, Rate, 
> > MTU, PathBits (LMC bits).
> > So if traditionally we had PathRecord requested for each Src->Dst port 
> > now we will need to track at least:
> > Src->Dst * #QoS-levels. (a non optimal implementation will require even 
> > more: #Src->Dst * #Clients * #Servers * #Services).
> 
> I understand you now.

I'm not sure about the granularity this needs tracking at.

> Can someone familiar with the opensm code tell me how difficult it would be to 
> extract out the code that tracks the subnet data and responds to queries?

Although I don't think that is difficult, IMO it is more a matter of
whether you want to buy into the architecture with the component and
vendor libraries. I can help with this if this is the direction chosen.
I would make this another build option.

The other question is how this would be changed so that when the data is
not present the real SA is queried.

-- Hal