The automotive industry is rapidly transitioning from Software-Defined Vehicles (SDV) to AI-Defined Vehicles (AiDV). During this transition, in-vehicle workloads are broadly categorized into two types:
- Best-effort workloads: Cloud-native services like infotainment and OTA updates with relaxed timing constraints
- Real-time workloads: Safety-critical tasks such as ADAS sensor fusion, motion control, and vehicle dynamics that must meet strict timing constraints
Eclipse Pullpiri serves as a vehicle workload orchestrator responsible for service lifecycle management and policy-based deployment. However, Pullpiri alone cannot guarantee deterministic execution for safety-critical workloads.
LG Electronics has been developing the Timpani Framework since 2025 to address the timing guarantee requirements for Pullpiri orchestrator's real-time workloads. We propose this project to the Eclipse Foundation to share this technology with the open source community and enable its adoption across the SDV/AiDV ecosystem.
Eclipse Timpani provides a real-time scheduling submodule for the Eclipse Pullpiri workload orchestrator, providing a framework that guarantees deterministic execution of safety-critical workloads.
In-Scope:
- Time-Triggered Scheduling: Periodic task execution based on static schedule tables (Signal-driven dispatch)
- Distributed Architecture: Timpani-O (orchestration bridge) and Timpani-N (node executor) components
- eBPF-based Monitoring: Non-intrusive scheduler observability (wakeup latency, execution time tracking)
- Deadline Miss Detection and Reporting: Detection and notification of real-time task deadline violations
- Pullpiri Integration: Integration with Pullpiri orchestrator via gRPC-based communication
- RT Linux Support: Real-time scheduling on PREEMPT_RT patched kernel environments
- Declarative Configuration: YAML-based task and schedule table configuration
Out-of-Scope:
- General-purpose RTOS development (focus on Linux kernel-based solutions)
- High-level workload orchestration (Pullpiri domain)
- Hardware-specific driver development
- Functional Safety Certification itself
Eclipse Timpani is a real-time scheduling framework designed for AI-Defined Vehicle (AiDV) applications. As a submodule of the Eclipse Pullpiri orchestrator, Timpani focuses on ensuring deterministic execution of real-time workloads where timing predictability is critical.
Timpani implements Time-Triggered Scheduling based on Time-Triggered Architecture (TTA) principles, proven approaches used in avionics and automotive safety-critical systems, executing tasks based on static schedule tables at predetermined periods with strict timing guarantees. The framework leverages Linux real-time scheduling policies (SCHED_FIFO, SCHED_RR) for priority-based task management, while providing eBPF-based observability for non-intrusive monitoring of scheduler behavior including wakeup latency and execution statistics.
The distributed architecture separates orchestration (Timpani-O) and execution (Timpani-N) components, enabling Pullpiri to manage real-time workloads across multiple nodes through declarative YAML-based configuration.
Key Features:
- Time-Triggered Execution: Deterministic periodic task dispatching
- Distributed Architecture: Separation of global scheduler (O) and node executor (N)
- eBPF Observability: Runtime visibility into scheduling behavior with minimal overhead
- Pullpiri Integration: Seamless orchestrator integration via gRPC services
- Mixed-Criticality Support (Planned): Coexistence of workloads with varying safety levels
"The existing codebase for the initial contribution contains a mix of code licensed under the Apache Software License 2.0 and The MIT License.
Furthermore, please note that the project includes an eBPF program (timpani-n/src/schedstat.bpf.c) which is dual-licensed under MIT OR GPL-2.0-only. The Dual MIT/GPL (or GPL) license string currently embedded in the eBPF source code is strictly a technical requirement to pass the strict Linux kernel's eBPF verifier. The Eclipse Foundation can seamlessly consume and distribute this specific component under the terms of the highly permissive MIT License alongside the rest of the project."
Trademark:
- The name "Timpani" is not currently registered as a software-related trademark by LG Electronics.
- The name is derived from the orchestral percussion instrument (timpani), signifying that Timpani provides the timing foundation for Pullpiri just as timpani drums provide the rhythmic foundation for an orchestra.
- We do not anticipate issues with trademark transfer to the Eclipse Foundation.
License Compatibility:
- All third-party dependencies use EPL-2.0 compatible licenses:
- gRPC: Apache 2.0
- Protocol Buffers: BSD-3-Clause
- libbpf: GPL-2.1 or BSD-2-Clause (dual license)
- systemd/libsystemd: LGPL-2.1+
- There are no problematic license combinations.
Cryptography:
- The current codebase does not contain cryptographic software.
- Secure communication via gRPC/TLS may be added in the future, and relevant regulations will be followed if so.
Patents:
- There are no known patent issues.
- LG Electronics will provide necessary patent licenses for the initial contribution.
Value brought to the Eclipse SDV Community:
- Pullpiri Ecosystem Completion: Eclipse Timpani serves as an essential submodule for the Eclipse Pullpiri orchestrator, adding deterministic execution capabilities for real-time workloads that Pullpiri alone cannot achieve.
- Filling the Open Source RT Gap: Currently, there is no "Open Source + Safety-grade Real-time" combination solution in the SDV space. Commercial solutions (Apex.OS, TTTech) are expensive, and ROS2 lacks safety guarantees. Timpani fills this gap.
- SDV/AiDV Standardization Contribution: Provides a real-time scheduling reference implementation aligned with the Eclipse SDV Working Group's vision.
- Vendor-Neutral Collaboration: Under Eclipse Foundation's vendor neutrality, multiple OEMs and Tier-1s can jointly evolve the project.
Value expected from hosting here:
- Community Contributions: Technology advancement through adoption and contributions from academic research and industry R&D
- Ecosystem Integration: Seamless integration with Pullpiri and other Eclipse SDV projects
- Safety Certification Support: Improved quality of functional safety reference implementation through community review and feedback
- SOAFEE Alignment: Alignment with automotive standardization groups through Eclipse SDV
Planned functionality for the next 12-18 months:
Phase 1 (Q1-Q2 2026): Foundation Building
- Rust migration of existing C/C++ codebase (enhanced memory safety)
- Communication infrastructure transition from D-Bus to gRPC
- Common Protocol Buffer definition standardization with Eclipse Pullpiri
Phase 2 (Q3 2026): Feature Expansion
- 4-layer hierarchical scheduling design (L1: RT Critical ~ L4: Best Effort)
- Mixed-Criticality workload support
- Enhanced temporal isolation mechanisms
Phase 3 (Q4 2026 ~ 2027): Platform Extension
- QNX RTOS porting (leveraging POSIX compatibility layer)
- NPU/GPU AI workload scheduling support
- Predictable execution guarantees for AI inference workloads
Community Growth Activities:
- Presentations at Eclipse SDV Community Day events
- Regular community meetings and technical workshops
- Research collaboration with academic institutions
- Documentation and tutorial improvements
Our primary scheduling objective is to establish the open-source infrastructure, complete the initial IP review smoothly, and quickly align with the parent project (Eclipse Pullpiri) ecosystem.
- May 2026: Project Provisioning & Initial Contribution
- Complete Eclipse project creation and establish working infrastructure (GitHub repositories, mailing lists, CI/CD pipelines).
- Submit the initial C/C++ codebase (Timpani-O, Timpani-N, libtrpc) to the Eclipse IP team for clearance (CQ).
- Push the initial codebase to the official repository upon IP approval.
- July 2026: First Milestone Build & Technology Transition
- Publish the first automated public build (v0.1.0 Milestone 1) based on the initial contribution.
- Kick-off the Rust migration (for memory safety) and transition from D-Bus to gRPC.
- October 2026: First Official Release & Integration (v0.5.0)
- Release v0.5.0 featuring the new gRPC interfaces and standardized Protocol Buffers.
- Demonstrate and document seamless integration with the parent Eclipse Pullpiri orchestrator.
- Early 2027: Advanced Features & v1.0 Baseline
- Implement the 4-layer hierarchical scheduling and mixed-criticality workload support.
- Release Timpani v1.0.0 targeting production-level stability and broad community adoption, followed by platform extensions (e.g., QNX, AI workloads).
Code Description:
The initial contribution consists of core components of the Timpani Framework developed by LG Electronics:
- Timpani-O (Global Scheduler/Orchestration Bridge)
- C++17 implementation, approximately 5,000 LoC
- gRPC server interface with Pullpiri
- Schedule table generation & distribution to Timpani-N nodes
- Deadline miss fault aggregation and reporting
- D-Bus/libtrpc based inter-node communication
- Timpani-N (Node Executor / time-trigger)
- C implementation, approximately 3,000 LoC
- Time-triggered task dispatching
- eBPF-based scheduler monitoring (sigwait, schedstat)
- Deadline miss detection and reporting to Timpani-O
- RT Linux scheduling policy support
- libtrpc (RPC Library)
- C implementation, approximately 1,000 LoC
- D-Bus based peer-to-peer communication
- Serialization/deserialization utilities
Copyright:
"All code is copyrighted by LG Electronics and will be contributed under the Apache Software License 2.0 upon transfer to the Eclipse Foundation."
Community:
The code has been developed internally at LG Electronics. We plan to actively encourage external contributor participation after Eclipse Project creation.
Third-Party Libraries:
- gRPC (version 1.50+, Apache 2.0 license): Used for RPC communication with Pullpiri.
- Protocol Buffers (version 3.x, BSD-3-Clause license): Used for message serialization.
- libbpf (version 1.0+, LGPL-2.1 OR BSD-2-Clause dual license): Used for eBPF program loading.
- libsystemd (LGPL-2.1+ license): Used for D-Bus communication.
- CMake (version 3.5+, BSD-3-Clause license): Used as the build system.
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