TiKV is an open-source, distributed, and transactional key-value database. Unlike other traditional NoSQL systems, TiKV not only provides classical key-value APIs, but also transactional APIs with ACID compliance. Built in Rust and powered by Raft, TiKV was originally created by PingCAP to complement TiDB, a distributed HTAP database compatible with the MySQL protocol.
The design of TiKV ('Ti' stands for titanium) is inspired by some great distributed systems from Google, such as BigTable, Spanner, and Percolator, and some of the latest achievements in academia in recent years, such as the Raft consensus algorithm.
If you're interested in contributing to TiKV, or want to build it from source,
see CONTRIBUTING.md. For maintainership-oriented code
reading and review context, see
doc/maintenance-guides/README.md.
TiKV is a graduated project of the Cloud Native Computing Foundation (CNCF). If you are an organization that wants to help shape the evolution of technologies that are container-packaged, dynamically-scheduled and microservices-oriented, consider joining the CNCF. For details about who's involved and how TiKV plays a role, read the CNCF announcement.
With the implementation of the Raft consensus algorithm in Rust and consensus state stored in RocksDB, TiKV guarantees data consistency. Placement Driver (PD), which is introduced to implement auto-sharding, enables automatic data migration. The transaction model is similar to Google's Percolator with some performance improvements. TiKV also provides snapshot isolation (SI), snapshot isolation with lock (SQL: SELECT ... FOR UPDATE), and externally consistent reads and writes in distributed transactions.
TiKV has the following key features:
Geo-Replication
TiKV uses Raft and the Placement Driver to support Geo-Replication.
Horizontal scalability
With PD and carefully designed Raft groups, TiKV excels in horizontal scalability and can easily scale to 100+ TBs of data.
Consistent distributed transactions
Similar to Google's Spanner, TiKV supports externally-consistent distributed transactions.
Coprocessor support
Similar to HBase, TiKV implements a coprocessor framework to support distributed computing.
Cooperates with TiDB
Thanks to the internal optimization, TiKV and TiDB can work together to be a compelling database solution with high horizontal scalability, externally-consistent transactions, support for RDBMS, and NoSQL design patterns.
Governance
See Governance.
Documentation
For instructions on deployment, configuration, and maintenance of TiKV,see TiKV documentation on our website. For more details on concepts and designs behind TiKV, see Deep Dive TiKV.
Note:
We have migrated our documentation from the TiKV's wiki page to the official website. The original Wiki page is discontinued. If you have any suggestions or issues regarding documentation, offer your feedback here.
TiKV adopters
You can view the list of TiKV Adopters.
TiKV software stack
- Placement Driver: PD is the cluster manager of TiKV, which periodically checks replication constraints to balance load and data automatically.
- Store: There is a RocksDB within each Store and it stores data into the local disk.
- Region: Region is the basic unit of Key-Value data movement. Each Region is replicated to multiple Nodes. These multiple replicas form a Raft group.
- Node: A physical node in the cluster. Within each node, there are one or more Stores. Within each Store, there are many Regions.
When a node starts, the metadata of the Node, Store and Region are recorded into PD. The status of each Region and Store is reported to PD regularly.
Quick start
Deploy a playground with TiUP
The most quickest to try out TiKV with TiDB is using TiUP, a component manager for TiDB.
You can see this page for a step by step tutorial.
Deploy a playground with binary
TiKV is able to run separately with PD, which is the minimal deployment required.
- Download and extract binaries.
$ export TIKV_VERSION=v7.5.0
$ export GOOS=darwin # only {darwin, linux} are supported
$ export GOARCH=amd64 # only {amd64, arm64} are supported
$ curl -O https://tiup-mirrors.pingcap.com/tikv-$TIKV_VERSION-$GOOS-$GOARCH.tar.gz
$ curl -O https://tiup-mirrors.pingcap.com/pd-$TIKV_VERSION-$GOOS-$GOARCH.tar.gz
$ tar -xzf tikv-$TIKV_VERSION-$GOOS-$GOARCH.tar.gz
$ tar -xzf pd-$TIKV_VERSION-$GOOS-$GOARCH.tar.gz
- Start PD instance.
$ ./pd-server --name=pd --data-dir=/tmp/pd/data --client-urls="http://127.0.0.1:2379" --peer-urls="http://127.0.0.1:2380" --initial-cluster="pd=http://127.0.0.1:2380" --log-file=/tmp/pd/log/pd.log
- Start TiKV instance.
$ ./tikv-server --pd-endpoints="127.0.0.1:2379" --addr="127.0.0.1:20160" --data-dir=/tmp/tikv/data --log-file=/tmp/tikv/log/tikv.log
- Install TiKV Client(Python) and verify the deployment, required Python 3.5+.
$ pip3 install -i https://test.pypi.org/simple/ tikv-client
from tikv_client import RawClient
client = RawClient.connect(["127.0.0.1:2379"])
client.put(b'foo', b'bar')
print(client.get(b'foo')) # b'bar'
client.put(b'foo', b'baz')
print(client.get(b'foo')) # b'baz'
Deploy a cluster with Docker Compose
The easiest way to run a complete TiKV cluster (3 PD + 3 TiKV nodes) for development and testing is using Docker Compose. The setup uses pre-built TiKV and PD nightly images from Docker Hub, so no building is required.
Note: On macOS, use docker compose (space) instead of docker-compose (hyphen) in all commands.
- Start the cluster:
$ docker-compose up -d
# On macOS, use: docker compose up -d
- Check cluster status:
$ docker-compose ps
# On macOS, use: docker compose ps
- Access the cluster:
- PD endpoints:
127.0.0.1:23791, 127.0.0.1:23792, 127.0.0.1:23793
- TiKV status:
http://localhost:20181/status, http://localhost:20182/status, http://localhost:20183/status
For more details, see docker-compose.README.md.
Deploy a cluster with TiUP
You can see this manual of production-like cluster deployment presented by @c4pt0r.
Build from source
See CONTRIBUTING.md.
Client drivers
If you want to try the Go client, see Go Client.
Security
Security audit
A third-party security auditing was performed by Cure53. See the full report here.
Reporting Security Vulnerabilities
To report a security vulnerability, please send an email to TiKV-security group.
See Security for the process and policy followed by the TiKV project.
Communication
Communication within the TiKV community abides by TiKV Code of Conduct. Here is an excerpt:
In the interest of fostering an open and welcoming environment, we as
contributors and maintainers pledge to making participation in our project and
our community a harassment-free experience for everyone, regardless of age, body
size, disability, ethnicity, sex characteristics, gender identity and expression,
level of experience, education, socio-economic status, nationality, personal
appearance, race, religion, or sexual identity and orientation.
Slack
Join the TiKV community on Slack - Sign up and join channels on TiKV topics that interest you.
License
TiKV is under the Apache 2.0 license. See the LICENSE file for details.
Acknowledgments
- Thanks etcd for providing some great open source tools.
- Thanks RocksDB for their powerful storage engines.
- Thanks rust-clippy. We do love the great project.
一个开源的分布式事务型键值数据库。和传统的 NoSQL 系统不同,它不仅提供经典的键值 API,还提供符合 ACID 的事务 API。