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The 0.8.0 release was tagged on Fri Feb 6 2015 as git tag bdr-plugin/0.8.0. This release requires bdr-Pg bdr-pg/REL9_4_1-1 to support full BDR functionality.
Upgrading to 0.8.0 from 0.7.x requires a pg_dump and pg_restore or pg_upgrade because the on-disk format of the PostgreSQL database changed between 9.4beta2 and 9.4.0 final.
Significant features and improvements to BDR in this release include:
UDR (Uni-Directional Replication)
Replication Sets
Global sequence performance improvements
Improvements to conflict handling
Many robustness and testing improvements
Replication sets have been introduced. This new feature allows admins to specify sets of tables that each node should receive changes on. It is now possible to exclude tables that are not of interest to a particular node, or to include only a subset of tables for replication to a node. Replication sets can be used for data distribution, for data integration and for limited sharding.
The performance of global sequence voting has been greatly improved, especially at higher node counts. It is now less likely for transactions to fail because of global sequence exhaustion when the BDR group is under significant write load.
Many more DDL commands can be replicated. Fixes have been applied for issues with replicating a few of the previously supported commands.
DDL commands that will cause full table rewrites are detected and prohibited early.
Commands that are disallowed on normal tables are now permitted on temp tables, including CREATE TABLE ... AS SELECT ....
User defined conflict handlers can now return replacement tuples for UPDATE/DELETE conflicts.
User defined conflict handlers are invoked for DELETE/DELETE conflicts.
Spurious conflicts are no longer logged after node initialisation.
The BDR source code has been split into two parts: a set of patches to PostgreSQL 9.4 and a separate PostgreSQL extension. This helps streamline work on integrating the features BDR requires into core PostgreSQL for releases 9.5 and onward.
The patched PostgreSQL is now tracked in git branches prefixed with bdr-pg/, mainly bdr-pg/REL9_4_STABLE. The extension is now tracked in git branches prefixed with bdr-plugin/, mainly bdr-plugin/stable (last stable release) and bdr-plugin/next (current development tree). All branches share the same working repository.
Prior releases of the BDR plugin were in the contrib/bdr subdirectory of the patched PostgreSQL source tree instead.
Permit the 'bdr' output plugin to be used from the SQL interface for logical replication. This is primarily useful for debugging.
Less memory is required to replay and apply large transactions.
The bdr_get_local_nodeid() function is available to return the local node's (sysid,timeline,dboid) tuple.
The bdr_version_num() and bdr_min_remote_version_num() functions were added. See SQL functions.