postgres_cluster

Various experiments with PostgreSQL clustering perfomed at PostgresPro.

This is a mirror of postgres repo with several changes to the core and a few extra extensions.

Core changes:

• Transaction manager interface (eXtensible Transaction Manager, xtm). Generic interface to plug distributed transaction engines. More info on postgres wiki and on the email thread.
• Distributed deadlock detection API.
• Logical decoding of transactions.

New extensions:

The following table describes the features and the way they are implemented in our four main extensions:

	commit timestamps	snapshot sharing
distributed transactions	pg_tsdtm	pg_dtm
multimaster replication	mmts	multimaster

mmts

An implementation of synchronous multi-master replication based on commit timestamps.

multimaster

An implementation of synchronous multi-master replication based on snapshot sharing.

pg_dtm

An implementation of distributed transaction management based on snapshot sharing.

pg_tsdtm

An implementation of distributed transaction management based on commit timestamps.

arbiter

A distributed transaction management daemon. Used by pg_dtm and multimaster.

raftable

A key-value table replicated over Raft protocol. Used by mmts.