This is an insert performance test implemented by running just inserts with mysqlslap against 1-3 node MySQL/Galera clusters. The results show how multi-master cluster can process more inserts than single native MySQL 5.1.38 server.
Our test session with Demo-2 release got somewhat prolonged. We faced few issues, mostly due to merging with MySQL head (5.1.31 - 5.1.32) and we needed to feed fixes through R&D cycle, which inevitably takes some time.
Our MySQL integration code (wsrep: https://launchpad.net/codership-mysql) was lagging behind from MySQL 5.1 release cycle and we needed to catch up eventually. MySQL/Galera Demo-1 was built on top of MySQL 5.1.30 and since then both 5.1.31 and 5.1.32 have been published.
MySQL 5.1 introduces new system variables (auto_increment_increment, auto_increment_offset) for managing auto increment 'sequences'. Using these variables, it is possible to set up a multi master replication environment, where auto increment sequences in each master node interleave, and no conflicts should happen in the replication. No matter which master(s) get the INSERTs.
Experiences with Demo 1 release has surfaced some issues, which we will address in the forthcoming "Demo 2 Release".
Here is the the list of changes that are coming in:
wsrep API releases version 2.0.0, which is now integrated
Conversion of (write) locking sessions to transactions. There is a system variable: wsrep_convert_LOCK_to_trx to enable/disable this conversion
We were running Drupal benchmarks to measure the performance of Drupal/Galera cluster and were surprised to find locking sessions (LOCK TABLES...UNLOCK) in the SQL profile. Locking sessions were left out of Galera supported feature set, but now we need to re-consider our policy a bit.
The life cycle of nerd contains an inevitable empty phase after all the hectic crunching to get release out is over. Nerd-work, is actually not so different from carpenter, artisan - a violin builder for instance. When the instrument is ready, there is nothing much to do, but to watch it dry. He cannot play with those thick fingers and ears, which don't make difference between flats and sharps.
During recent days, Guys have been singing the "release" song in the office. We had set internal milestone to get the Galera demo version released around the year end and the effort to complete release, is getting pretty strong at the moment. Anyway, soon it is not relevant to talk about year end anymore.
English
Finnish