Skip to content
Open access

Job-Level Dynamic Cache Allocation for Real-Time Systems under Shared LLC Interference

Aug 2026 · ACM Transactions on Embedded Computing Systems · 0 citations · 9 references

TL;DR

This paper introduces a job-level dynamic cache allocation strategy for multicore systems in which critical real-time tasks execute on a dedicated core while sharing the LLC with best-effort workloads executing on the remaining cores.

Abstract

Efficient management of shared cache resources is a key challenge in multicore real-time systems. Mechanisms such as Intel’s Cache Allocation Technology (CAT) enable software control over last-level cache (LLC) partitions, providing opportunities to reduce interference and tighten worst-case execution time (WCET) bounds. Existing approaches typically rely on static cache allocation, which can lead to over-provisioning and inefficient cache usage. This paper introduces a job-level dynamic cache allocation strategy for multicore systems in which critical real-time tasks execute on a dedicated core while sharing the LLC with best-effort workloads executing on the remaining cores. We formulate the allocation problem as a constraint-based optimization model that simultaneously enforces schedulability constraints, cache capacity limits, and preemption-induced concurrency. By allocating and releasing cache partitions at job boundaries, our approach adapts to temporal variations in job activity, minimizing the cache dedicated to critical tasks while preserving their schedulability. Through evaluation on synthetic task sets, we show that job-level dynamic allocation improves schedulability and systematically increases the cache available to non-critical tasks compared to task-level static or dynamic strategies. Moreover, it often requires fewer allocation operations, indicating that increased flexibility does not entail higher runtime overhead. These results demonstrate that job-level cache allocation is a promising direction for efficient and predictable resource management in multicore real-time systems.

Read PDF

Similar papers

Preprint Aug 2026

Beyond the Limits: Flexible and Congestion-Aware Cluster Scheduling for the Cloud

The results show that soft SLO limits reduce corrective rescheduling actions by 49% compared to hard-limit approaches while maintaining acceptable performance guarantees, and resource-aware scheduling decreases node-level congestion and further mitigates SLO violations, demonstrating the effectiveness of incorporating application-level flexibility and hardware-level insights into scheduling and rescheduling decisions.

Oliver Larsson, Thijs Metsch, Cristian Klein et al. · 0 citations
Conference 2026

Uncertainty-Aware Resource Allocation for Multi-Path Programs with In-Kernel Predictions

Experimental results on SPEC CPU benchmarks show that MPORA delivers accurate predictions under unseen inputs and distribution shifts with low overhead, while improving schedulability and response times over existing methods.

Abby Eisenklam, G. CarlosA.Montenegro, Xian Wang et al. · 0 citations
Conference 2026

CacheFlow: Using Maximum Flow to Bound Cache-Based Preemption Delays

CacheFlow is presented, a framework that formulates total CRPD as a maximum-flow problem, and an iterative max-flow formulation is described to more efficiently integrate the max-flow solving in the context of standard fixed-priority response-time analysis.

Tiancheng He, Bryan C. Ward · 0 citations
Open access Aug 2026

Hierarchical Scheduler with Adaptive Time-Budget Reallocation for Time-Triggered Edge-Fog-Cloud Architectures

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. · 0 citations
Conference Jul 2026

FlowGuard: Slack-Aware Overload Control for Multi-Agent LLM Serving

Multi-agent applications increasingly rely on shared large language model backends in the public cloud, where bursty workloads cause requests from different agents to contend for the same LLM instances, leading to long queues, memory imbalance, and severe tail-latency inflation. Existing approaches typically prioritize requests using coarse workflow positions or static execution heuristics, which fail to adapt to short-term overload dynamics. We present FlowGuard, a workflow-aware overload controller for multi-agent LLM serving. Its key insight is that under sustained overload, GPU cycles spent on requests whose execution service-level-objectives (SLOs) are already violated are wasted. FlowGuard continuously recomputes per-request slack and prioritizes requests with the greatest remaining time before their deadlines, thereby maximizing on-time completions. In addition, a resource-aware dispatcher jointly accounts for KV-cache memory pressure and in-flight queue depth to reduce preemption across shared instances. Evaluated on a deliberately over-subscribed two-GPU backend, where all policies exhibit high absolute miss rates (i.e., the percentage of workflows that miss their deadlines), FlowGuard reduces the miss rate by 14–28% points over workflow-oblivious and static-priority baselines under BurstGPT-driven load, and by 34–38% points under co-located mixed-agent workloads.

Ali Zafar Sadiq, Hai-Ying Shen · 0 citations

We use cookies to run the site and, with your consent, for analytics and to show ads. See our Cookie Policy.