Open Virtual Machine Spec (OVMS) v0.1

Mission

OVMS defines a portable specification for packaging, distributing, and running full-virtual-machine artifacts (disk layers, kernel/initrd, and optional RAM snapshots) with a small runtime contract. This enables any runtime to be a drop-in for orchestrators like Huo, supporting fast boot, layering, and OCI compatibility for distribution.

Quickstart

1. Create Manifest: Use the JSON schema in schemas/manifest.v1.json to define your VM artifact.
2. Build Artifact: Package kernel, initrd, disk layers, and RAM snapshot as OCI blobs (use tools like skopeo for OCI push).
3. Push to Registry: Push to OCI registry (e.g., Docker Hub, private).
4. Pull and Run: Use CLI ovm pull <ref> to fetch, then ovm run <ref> to start.
5. Snapshot: ovm snapshot <instance> -t <tag> to create RAM snapshot.
6. Integrate with Huo: Use RuntimePlugin in Huo to dispatch OVMS workloads to VMM plugins (e.g., Hypr adapter).

Overview

OVMS reuses OCI for distribution (manifests as OCI image manifests with custom media types). Artifacts are layered for efficiency: base disk + diffs + optional RAM snapshot for <10ms boots. Runtimes expose a minimal HTTP API for control. Huo integrates as the reference orchestrator via RuntimePlugin interface.

See rfc/ovms-v0.1.md for full spec.

Components

• Manifest: JSON describing artifact (see examples/ubuntu-manifest.json).
• Runtime Contract: HTTP endpoints for start/stop/snapshot/status (see rfc/ovms-v0.1.md).
• CLI: ovm tool for pull/run/snapshot (see cli/ovm).
• Adapters: Mappings for runtimes like Cherrybomb (see runtimes/cherrybomb-adapter.md).
• Hacks: OCI compatibility notes (see hacks/oci-compat.md).

Security

• Sign manifests with Cosign.
• Runtimes use namespaces, seccomp for isolation.
• RAM snapshots opt-in with mlock for latency guarantees.

Limitations v0.1

• Linux x86_64 only.
• BIOS boot (UEFI v0.2).
• No GPU; basic devices (IVSHMEM).

For Huo integration, see Huo's RuntimePlugin interface in pkg/plugin.