OpenHFT/Chronicle-Map Replication

tech

Preparation

Key points

  • Enterprise Edition feature

  • It’s TCP/IP Replication

  • TCP/IP Throttling - only broadcasts the latest update of each entry

How Chronicle Map Replication works

  1. Refer to an instance of a remote map as a node. Each node can be connected to up to 128 other nodes.

  2. each remote map mirrors its changes over to another remote map.

  3. Neither map is considered to be the master store of data.

  4. Each map uses timestamps to reconcile changes, When the timestamps are the same, the remote node with the smaller identifier will be preferred.

Multiple Processes on the same server with Replication

  • exchange data via shared memory - rather than by TCP or UDP replication.

  • Only one instance is set up TCP or UDP replicated - if the TCP replicated Chronicle Map instance received an update from a remote node, then this update would be immediately available to all the instances of Chronicle Map on the server

Identifier for Replication

  • must have their identifiers set - if you wish to replicate data between two or more server. otherwise all of the Chronicle Map instances not actively participating in TCP or UDP replication.

  • identifier must be unique to each server -

    • Each ChronicleMap on the same server must have the same identifier.

    • Chronicle Map replication ignores updates which have originated from itself.

Replication event logging

  • can be configured to log all replication events to a Chronicle Queue for auditing purposes.

  • Currently, a map can be configured to log all outgoing events that it sends to remote peers.