Re: openldap.git branch mdb updated. 5d600468011aaf773cf4cd7ed13a213d3e2e72ca

At this point the libmdb library code is behaving pretty well, and the back-mdb is code-complete. It is not yet passing all of make test, but it does pass the majority of tests so far. As expected, it delivers higher throughput than back-bdb/hdb under heavy load, with a smaller memory footprint, and nothing to tune. So far so good. Remaining bugs revealed by the test suite need to be tracked down, then some profiling/optimization work should be done. The current code is already fast, but it is far from optimal. TODO: * the mdb library doesn't coordinate cursors with write operations. (So performing a write invalidates any open cursors in the same txn.) This needs to be fixed. * cursors only support read operations. The back-mdb indexer would benefit from being able to use put/del on a cursor, as back-bdb does. (And the back-bdb/hdb code needs to be revisited; it closes/re-opens cursors very often when it probably should just open once and keep using till an operation is done. Of course this has to be balanced against the desire to keep BDB resources locked for as little time as possible. Fortunately since MDB has no locks the same worries don't apply.) * entry_encode/decode re-work - currently back-mdb uses the same encoder as back-bdb/hdb. I plan to replace this with an encoding that uses a separate database of attributeDesc to integer mappings. This will reduce the overall DB size and will accelerate decoding. I'm backing away from the idea of a fully persistent DB with no encoding/decoding at all; maybe will try this further down the road. (The full in-memory structures are quite large, and DB size will increase dramatically. But this might be OK overall; or we might look at shrinking slapd's Entry structure etc. - quite a huge amount of grunt work involved.) openldap-commit2devel(a)OpenLDAP.org wrote: -- -- Howard Chu CTO, Symas Corp. http://www.symas.com Director, Highland Sun http://highlandsun.com/hyc/ Chief Architect, OpenLDAP http://www.openldap.org/project/