dbShards/Replicate is a complete replication and failover solution for enterprise databases, including MySQL, Postgres and others. dbShards/Replicate uses patent-pending Out-of-Band (OoB) technology to deliver high performance yet reliable multi-threaded replication for High Availability (HA), dramatically improving write performance and mitigating “replication lag”.
With dbShards Out-of-Band (OoB) replication technology, transactions are written in parallel to the primary database and to a primary replication agent. The primary replication agent replicates transactions to a secondary agent process before the transaction is committed to the primary database. This guarantees that the transaction is on (at least) two servers so that no transactions are lost if the primary server fails.
The secondary replication agent then asynchronously applies the transactions in parallel streams to the slave database resulting in minimal replication lag compared to typical single-threaded replication capabilities offered by DBMS vendors.
Replication Overview
As each SQL statement is executed in the application, the dbShards driver asynchronously sends the SQL to the primary replication agent in parallel to executing the SQL against the primary database. The primary replication agent asynchronously sends the SQL to the secondary replication agent. When the application issues a commit statement, the driver performs a synchronous communication with the primary replication agent to ensure that the transaction details have been received by both the primary and secondary agent. Once the driver receives an ACK then the transaction is committed to the database.
If the server hosting the primary database were to fail at this point, dbShards can failover to the secondary server without transaction loss.