[openib-general] [PATCH 0/4] SA path record caching

[Hal Rosenstock]

On Tue, 2006-01-31 at 12:44, Sean Hefty wrote:
> Or Gerlitz wrote:
> > Why not having a failed lookup as the --only-- trigger to update the 
> > cache? so the cache contains only paths that were demanded by some 
> > consumer. What is implementation you were considering, is it an SA 
> > replica having all those paths whose sgid is the local node gid?
> 
> I view MPI as one of the primary reasons for having a cache.  The cache is 
> updated using an SA GET_TABLE request, which is more efficient than sending 
> separate SA GET requests for each path record.  Waiting for a failed lookup to 
> create the initial cache would delay the startup time for apps wanting 
> all-to-all connection establishment.  In this case, we also get the side effect 
> that the SA receives GET_TABLE requests from every node at roughly the same time.
> 
> Your assumption is correct.  The implementation will contain copies of all path 
> records whose SGID is a local node GID.  (Currently it contains only a single 
> path record per SGID/DGID, but that will be expanded.)

Ultimately, this should likely be using MultiPathRecord as it is able to
do some things PathRecords can't.

-- Hal