[openib-general] SA cache design

[Sean Hefty]

Grant Grundler wrote:
> I forgot to point out postgres:
> 	http://www.postgresql.org/about/

This looks like it would work well.

The question that I have for users is:  Is it acceptable for the cache to make 
use of a relational database system?

The disadvantage is that a RDMS would need to be installed and configured on 
several, or all systems.  (It's not clear to me yet how much of that could be 
automated.)

The advantage is that the cache would gain the benefits of having a database 
backend - notably support for more complex queries, persistent storage, and 
indexing to increase query performance.

To provide some additional context, path record queries can be fairly complex, 
involving a number of fields.  (All queries today are limited to sgid, dgid, and 
pkey.)  Trying to efficiently retrieve a path record based on a dgid and pkey is 
non-trivial, and support for queries with additional restrictions or for other 
SA records complicates this issue.

- Sean