etcd vs TiKV

etcd is an open-source, strongly consistent distributed key-value store for data used by distributed systems and clusters of machines. It arranges values in hierarchical directories and lets clients watch keys or directories for changes. Clients can read and write values with standard HTTP tools such as curl, and keys may have optional time-to-live expiration. The project uses the Raft protocol and handles leader elections during network partitions, including when a leader machine fails. etcd is a core Kubernetes component and its primary datastore. The project provides pre-built binaries, source builds, and container images. Linux on AMD64 and ARM64 is tier 1; Darwin and Windows on either architecture are tier 3, and other platforms are unsupported. TLS and client-certificate authentication are supported for client and peer connections, but neither is enabled by default. The software is self-hosted and licensed under Apache 2.0, with a listed price of free. The integrations listing includes Kubernetes, CoreDNS, and language client libraries, while warning that third-party tools and libraries there are not tested or maintained by the etcd team.

TiKV is a distributed transactional key-value database designed as a unified storage layer across nodes. It provides a raw key-value API and a transactional key-value API with ACID semantics, but those APIs cannot both be used on the same keyspace. The project says it can support petabyte-scale deployments spanning trillions of rows. Raft groups replicate data across nodes for fault tolerance, while horizontal scaling and rebalancing support changes in cluster capacity. RawKV also includes time-to-live expiration and compare-and-swap operations. The documentation lists Java, Go, Rust, Python, and C++ clients; Java and Go are marked stable, while the others are marked unstable. TiKV is self-hosted and Apache 2.0 licensed, with Linux, macOS, Windows, and API listed as platforms. Its documentation describes TLS for network connections and configurable encryption at rest, including AES methods. TiKV was originally created by PingCAP and is a Cloud Native Computing Foundation graduate project. The community page recommends Slack for general communication and provides a dedicated mailing list for security vulnerability reports.