Features
Data Replication
Replication in CrateDB allows users to replicate data across multiple nodes in a cluster. Data is replicated at the shard level, and replica shards automatically step in as primary shards if the primary one becomes unavailable due to failures or maintenance. Maintaining at least two replicas is recommended to ensure high availability of the CrateDB cluster.
Replication helps increase performance with parallel data query and data availability. Read requests are broken down and executed in parallel across multiple shards on multiple nodes, massively improving read performance.
CrateDB offers multiple configuration options to find the optimal balance between shards, partitions, and replications:- Partitioning and sharding help scale the cluster horizontally and optimize hardware usage during ingest and read. Ingest and query workloads are parallelized and distributed across the whole cluster.
- Replication helps optimize the resiliency of the cluster and allow for higher read throughput.
CREATE TABLE t1 ( name STRING ) CLUSTERED INTO 3 SHARDS WITH (“number_of_replicas” = '1');
Additional resources
CrateDB at Berlin Buzzwords 2023
When milliseconds matter: maximizing query performance in CrateDB.
Timestamp: 9:55 – 10:35