ab5df57ecf
When snapshot store requests raft snapshot from etcdserver apply loop, it may block on the channel for some time, or wait some time for KV to snapshot. This is unexpected because raft state machine should be unblocked. Even worse, this block may lead to deadlock: 1. raft state machine waits on getting snapshot from raft memory storage 2. raft memory storage waits snapshot store to get snapshot 3. snapshot store requests raft snapshot from apply loop 4. apply loop is applying entries, and waits raftNode loop to finish messages sending 5. raftNode loop waits peer loop in Transport to send out messages 6. peer loop in Transport waits for raft state machine to process message Fix it by changing the logic of getSnap to be asynchronously creation. |
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| Documentation | ||
| Godeps | ||
| client | ||
| discovery | ||
| error | ||
| etcdctl | ||
| etcdctlv3 | ||
| etcdmain | ||
| etcdserver | ||
| hack | ||
| integration | ||
| logos | ||
| pkg | ||
| proxy | ||
| raft | ||
| rafthttp | ||
| scripts | ||
| snap | ||
| storage | ||
| store | ||
| tools | ||
| version | ||
| wal | ||
| .dockerignore | ||
| .gitignore | ||
| .godir | ||
| .header | ||
| .travis.yml | ||
| CONTRIBUTING.md | ||
| DCO | ||
| Dockerfile | ||
| LICENSE | ||
| MAINTAINERS | ||
| NOTICE | ||
| Procfile | ||
| README.md | ||
| ROADMAP.md | ||
| V3DemoProcfile | ||
| build | ||
| build.bat | ||
| cover | ||
| main.go | ||
| test | ||
README.md
etcd
Note: master branch may be in unstable or even broken state during development. Please use releases instead of master branch to get stable binaries.
etcd is a distributed, consistent key-value store for shared configuration and service discovery, with a focus on being:
- Simple: curl'able user facing API (HTTP+JSON)
- Secure: optional SSL client cert authentication
- Fast: benchmarked 1000s of writes/s per instance
- Reliable: properly distributed using Raft
etcd is written in Go and uses the Raft consensus algorithm to manage a highly-available replicated log.
See etcdctl for a simple command line client. Or feel free to just use curl, as in the examples below.
If you're considering etcd for production use, please see: production-ready.md
Getting Started
Getting etcd
The easiest way to get etcd is to install one of the pre-built binaries from the tagged releases: instructions are available on GitHub.
For those wanting to try the very latest version, you can build the latest version of etcd from the master branch.
You will first need Go installed on your machine (version 1.4+ is required).
All development occurs on master, including new features and bug fixes.
Bug fixes are first targeted at master and subsequently ported to release branches, as described in the branch management guide.
Running etcd
First start a single-member cluster of etcd:
./bin/etcd
This will bring up etcd listening on port 2379 for client communication and on port 2380 for server-to-server communication.
Next, let's set a single key, and then retrieve it:
curl -L http://127.0.0.1:2379/v2/keys/mykey -XPUT -d value="this is awesome"
curl -L http://127.0.0.1:2379/v2/keys/mykey
You have successfully started an etcd and written a key to the store.
Running local etcd cluster
First install goreman, which manages Procfile-based applications.
Our Procfile script will set up a local example cluster. You can start it with:
goreman start
This will bring up 3 etcd members infra1, infra2 and infra3 and etcd proxy proxy, which runs locally and composes a cluster.
You can write a key to the cluster and retrieve the value back from any member or proxy.
Next Steps
Now it's time to dig into the full etcd API and other guides.
- Explore the full API.
- Set up a multi-machine cluster.
- Learn the config format, env variables and flags.
- Find language bindings and tools.
- Use TLS to secure an etcd cluster.
- Tune etcd.
- Upgrade from 0.4.9+ to 2.2.0.
Contact
- Mailing list: etcd-dev
- IRC: #etcd on freenode.org
- Planning/Roadmap: milestones, roadmap
- Bugs: issues
Contributing
See CONTRIBUTING for details on submitting patches and the contribution workflow.
Reporting bugs
See reporting bugs for details about reporting any issue you may encounter..
Project Details
Versioning
Service Versioning
etcd uses semantic versioning New minor versions may add additional features to the API.
You can get the version of etcd by issuing a request to /version:
curl -L http://127.0.0.1:2379/version
API Versioning
The v2 API responses should not change after the 2.0.0 release but new features will be added over time.
32-bit systems
etcd has known issues on 32-bit systems due to a bug in the Go runtime. See #358 for more information.
License
etcd is under the Apache 2.0 license. See the LICENSE file for details.