From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nathaniel Rutman Date: Wed, 13 Feb 2008 10:23:50 -0800 Subject: [Lustre-devel] Global generic database Message-ID: <47B335B6.5010703@sun.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lustre-devel@lists.lustre.org The design of various new features in Lustre call for global (filesystem wide) databases, accessible from clients or other servers: A. pools - pool descriptions (pool #1 = OSTs 1-10,30-60), pool policies (all .jpg files to pool #1) B. filesets - fileset policies (log creates on fileset #1 to feed "foo") C. HSM - (aureleien - what was the use case here?) We've already implemented at least 2 of these: D. Fid Location Database - (is this done?) E. configuration parameters - stored in MGS llogs Rather than continue 1-off implementations, I think it's time we came up with a consistent, global, generic database mechanism for A-C as well as other future uses. Needs to be: 1. Fast. We need to cache database entries locally, which also means having them under locks. a. local caching b. locks 2. Generic. Store any kind of data, not limited to 8k page boundaries, etc. 3. Transactional. Power loss doesn't lead to inconsistent state. 4. Recoverable. Client changes are replayed if need be. 5. Remotely accessible, from a client or other servers.