Jul 2026· De Computis· Vol 15· 0 citations· 11 references
Computer Science
Abstract
As RISC-V processors are increasingly considered for embedded real-time and control-oriented systems, evaluating how timing behavior changes under increasing task concurrency becomes essential. Adding runnable tasks can amplify preemptions, context-switch activity, response-time variability, execution jitter, and deadline pressure. Existing RISC-V simulation and virtual-platform environments mainly target architectural exploration, functional validation, or full-system execution, and do not directly provide a controlled workflow for isolating scheduler-induced timing degradation across large configuration spaces. This paper presents nSim-RV, a configurable and reproducible RISC-V simulation and orchestration framework for scheduler-aware timing scalability evaluation. The framework combines automated campaign generation, deterministic workload configuration, structured dataset aggregation, duplicate validation, and timing-oriented metric extraction. The evaluation compares a standard shared-pipeline execution model with an nMPRA-inspired preserved-context mode under identical scheduler and workload conditions. The campaign includes CoreMark, Dhrystone, and a deterministic synthetic RT-Control workload, 2–32 concurrent tasks, 50 k–1 M cycle observation windows, cache-disabled and cache-enabled configurations, and four-stage and five-stage pipeline organizations, resulting in 864 validated configurations. Results show that increasing task concurrency amplifies timing variability and deadline pressure. Preserved-context execution reduces switching-induced disturbance and delays or reduces higher-pressure timing behavior in several trajectories. Under the five-stage cache-disabled RT-Control configuration at N = 32, it reduces the deadline miss ratio from 3.74% to 2.21%, corresponding to a 41.1% relative reduction, with the clearest benefits observed for Dhrystone and RT-Control at intermediate–high task counts.
The lack of determinism restricts the integration of safety-critical applications into Edge–Fog–Cloud (EFC) architectures. Existing EFC schedulers are typically designed for dynamic, best-effort operation based on unmanaged resource allocation and elastic virtualization. This paradigm introduces unbounded queueing, resource contention, and timing jitter, making standard schedulers unsuitable for hard-deadline workloads. Moreover, most approaches focus on computational placement, while communication is abstracted or treated as a secondary cost term. As a result, bounded-latency routing and deterministic task execution are rarely co-optimized under a unified timing model. This paper addresses these gaps by utilizing a managed Time-Triggered Edge–Fog–Cloud (TTEFC) architecture that supports safety-critical workloads, orchestrates IEEE Time-Sensitive Networking (TSN) for local intra-domain communication, and uses IETF Deterministic Networking (DetNet) for routed inter-domain paths. On this infrastructure, a hierarchical genetic algorithm (HGA) is proposed to jointly schedule partition-to-execution-location allocation, partition execution order, inter-partition route selection, and negotiated per-partition time budgets that act as temporal boundaries for parallel partition-level optimizers. An adaptive slack reallocation operator redistributes unused temporal slack from over-satisfied partitions to budget-violating partitions, improving feasibility convergence. Experiments on synthetic DAG workloads with 100–500 tasks compare the proposed HGA against HEFT and round-robin baselines. These baselines are included as scoped external references to contextualize the end-to-end scheduling performance of the proposed method. Ablation results show that slack reallocation improves partition-budget feasibility, reaches feasible budget assignments earlier, and produces tighter budget–makespan alignment than feedback-free and static-budget variants. An automotive-characteristic DAG case study further evaluates the method on an application-oriented workload under the same timing and communication assumptions.
Omar Hekal, Josepaul Paulachan, Daniel Onwuchekwa et al.· Future Internet· 0 citations
PeakBench is a benchmark of executable multi-tool workflows with execution-grounded dependency annotations and measured resource profiles that shows that strong logical planning does not reliably translate into safe or efficient execution under resource constraints, and exposes resource information to reduce avoidable overflows and improve resource utilization.
Zhi-Kai Chen, Xu-Xiang Zhong, Song-Yan Li et al.· 0 citations
A standards-based, multi-tenant cloud inference framework that integrates OpenStack orchestration with Single Root I/O Virtualization (SR-IOV)-enabled graphics processing unit (GPU) partitioning to achieve predictable and isolated real-time inference execution.
Rui Ma, Bingfeng Shi, Xin Ma et al.· Journal of ICT Standardizati...· 0 citations
Centralized automotive architectures increasingly consolidate compute-intensive workloads onto heterogeneous Multi-Processor System-on-Chip (MPSoC), creating strict execution, memory, and communication constraints. This paper presents RunSoC 2.0, a customizable framework for early-stage design-space exploration of task scheduling and allocation on heterogeneous MPSoCs. Building on RunSoC 1.0, which targeted allocation on homogeneous hardware, RunSoC 2.0 extends the framework to heterogeneous platforms by modeling processor-specific execution times, cluster-level organization, and domain-specific processing properties. It represents task sets as directed acyclic graphs (DAGs) subjected to strict end-to-end latency and core-affinity constraints, and formulates task scheduling and allocation as a multi-objective optimization problem that minimizes hierarchical memory-budget violations and inter-core/inter-cluster communication penalties. The framework supports multiple solving backends, including COIN-OR Branch and Cut (CBC), Google OR-Tools CP-SAT, and a Genetic Algorithm (GA), enabling comparative evaluation of exact, constraint-programming, and meta-heuristic approaches. We evaluate RunSoC 2.0 using synthetic automotive task sets ranging from 10 to 500 tasks, mapped to representative heterogeneous MPSoCs, including the Renesas R-Car V4H, NVIDIA Jetson AGX Orin, and TI TDA4VM. The results show that RunSoC 2.0 can generate feasible and optimal schedules, expose architectural bottlenecks, and support rapid comparison of platform alternatives. Notably, CP-SAT consistently outperforms both CBC and the GA across tightly constrained hard real-time scheduling instances. By incorporating cluster-aware communication and memory modeling, RunSoC 2.0 improves the realism of early-stage MPSoC analysis while retaining practical solution times for large automotive workloads. (..)
D. Krüger, Lucas Mauser, Stefan Wagner· 0 citations
The method lets an HPC site compare deployment strategies using both user-visible performance and scheduler impact, then select the fastest strategy within its own RPC-demand limit.
Nil Tianchen Mu, William Dizon, Glen Otero et al.· 0 citations
The emergence of modern agents powered by large language models has created a demand for executing long-horizon, autonomous workflows in various domains that require significant computational resources. While High Performance Computing clusters provide the ideal infrastructure for these computation-intensive workloads, traditional HPC job schedulers such as Slurm are not designed for dynamic, agentic workflows characterized by unpredictable task durations, external API calls, and fault tolerance requirements of modern agents. This work presents RASER, a user-space framework that enables seamless execution of agentic workflows on production HPC clusters by extending Slurm's internal primitives. RASER introduces agentic job arrays with work stealing via shared filesystem queues, user-space checkpointing through application-level state serialization combined with Slurm requeue, and Apptainer container-based isolation without requiring any image modifications. Evaluations demonstrate that RASER reduces makespan by nearly 39% compared to static partitioning while achieving near-full CPU utilization. RASER provides resilience against preemption and failures while maintaining minimal checkpoint/restore overhead. It requires no kernel privileges or external database infrastructure, making it an accessible solution for deploying agentic workflows on existing HPC infrastructure.
