Container Tool, Key-Value Store, Gets an Upgrade
The latest version of a distributed key-value platform used to store data in containers across a cluster of machines and previously integrated with the Kubernetes cluster manager includes API and data model features designed to ease upgrades while supporting a broader range of applications delivered via containers.
CoreOS, the San Francisco-based application container specialist, announced last week that version 3 of its open source key-store value dubbed etcd is generally available. The tool implements flexibility features like distributed coordination primitives and transactional memory. The upgrade also marks the first stable release of the etcd3 API and data model, the company noted in a blog post.
The key-value store system was originally designed to handle machine coordination issues for CoreOS updates. It has since been extended to distributed networking discovery, scheduling, data configuration and load balancing services. Upgrades to etcd also have moved in parallel with the popular Kubernetes cluster manager turned over to the open source community by Google (NASDAQ: GOOGL).
Google and CoreOS have worked hand-in-glove to build out the Kubernetes ecosystem as application containers move steadily into production. The goal, the partners said, is to make Kubernetes a "production-grade container management system for the cloud-native community."
Along with Google, other etcd users include Red Hat (NYSE: RHT), Japan's NTT (NYSE: NTT) and Chinese telecom giant Huawei (SHE: 002502). Red Hat, for example, is leveraging both Docker container components and the CoreOS key-value store tool in its OpenShift container application platform.
The CoreOS tool has evolved over the last several years into a key-value store with JSON format endpoints, the startup notes. Some features tended to be "chatty" with clients, placing quorum pressure on cluster when idling. Although etcd version 2 cloud adequately coordinated machines, the company explained, "Coordinating the proliferating micro-services in today’s infrastructure requires [a tool capable of] supporting tens of thousands of active clients operating on a million keys within a single cluster."
Hence, the base server interface on version 3 replaces JSON with the general RPC framework built on the HTTP/2 standard to boost efficiency. (Support for JSON endpoints was maintained through a gRPC gateway, CoreOS noted.) Native etcd3 clients communicate over a gRPC protocol.
Meanwhile, the new API incorporates a lightweight streaming lease "keepalive" model. The version 3 data model also eliminates explicit key hierarchies, replacing them with what CoreOS described as a "flat binary key space with transactional, multi-version concurrency control semantics."
CoreOS asserted that version 3 of its key-value store represents nothing less than a "conceptual leap" over the earlier version, incorporating a more efficient API that can scale beyond the evolving demand of current applications to future hyperscale clusters.
Project managers said their next steps include adding smart proxy feature to improve scaling along with protocol gateways for "custom etcd personalities."