OpenEBS is a CNCF sandbox project providing container-native persistent storage for Kubernetes. This repository is the project's coordination hub: it contains the umbrella Helm chart for deploying OpenEBS (LocalPV hostpath/LVM/ZFS and Mayastor replicated engines), the kubectl-openebs plugin binary for inspecting and managing volumes and nodes, and the openebs-upgrade job for Helm-based upgrades and Mayastor data-plane rolling restarts. It also houses the OpenEBS Enhancement Proposals (OEPs), CI/CD workflows, and release automation. The repo is primarily an application repository rather than a data/research repository; its many markdown design documents are engineering proposals, not analysis artifacts. The main entry points are plugin/src/main.rs, openebs-upgrade/src/bin/upgrade-job/main.rs, and charts/Chart.yaml. The upgrade path uses trait-based Helm upgraders and Kubernetes pre-upgrade hooks, while the plugin dispatches engine-specific operations through a common Operations enum. Externally, it depends on the Kubernetes API, Helm, and several engine submodules/repositories (Mayastor, localpv-lvm, localpv-zfs). Maintenance is active: the last commit is recent, Dependabot is configured, and the CI pipeline includes linting, image building, Trivy scanning, and release workflows. Technical drift is low overall, though the project's reliance on git submodules and Nix-pinned dependencies creates coordination risk across the broader OpenEBS ecosystem.
This repository implements the Virtual Data Optimizer (VDO) storage system, providing inline block-level deduplication, compression, and thin provisioning for Linux block devices. It consists of a kernel-level device-mapper target (not included in this repo) and user-space management tools. The core deduplication engine is the Universal Deduplication System (UDS) located in the utils/uds directory. Key user tools include vdoformat (volume creation), vdostats (statistics reporting), and various debugging/recovery utilities. The architecture is modular with clear separation between the UDS library, volume management layer, and command-line interfaces. The system integrates with LVM and is designed for enterprise storage environments requiring efficient data reduction.
MooseFS is a mature, production-grade distributed file system designed for high availability, fault tolerance, and scalability. Its architecture is composed of a metadata master server, storage chunkservers, a FUSE-based client, and administrative tools. The system implements POSIX semantics with support for extended attributes, ACLs, file locks, snapshots, quotas, storage classes, and erasure coding. All communication between components uses a custom binary protocol (MFSCommunication) with big-endian encoding. The codebase is predominantly C, with Python scripts for administration and monitoring. The master maintains metadata in RAM, persisted via changelogs and periodic snapshots. Chunk replication is configurable via goals and label-based topology. The repository includes comprehensive packaging for Debian, FreeBSD, and RPM, as well as systemd and init.d service files. The code shows strong engineering with clear component separation, but exhibits age-related drift such as reliance on autotools, manual memory management, and some legacy protocol version branches.