Searcharxiv⌕ Search

SEARCH · Searcharxiv

Results for “cs.OS”

Search indexed arXiv papers on artificial intelligence, large language models, computer vision and robotics. Read source abstracts and follow links to arXiv.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 847 records · Page 47Linked to original sources

Confidential Serverless Computing

Although serverless computing offers compelling cost and deployment simplicity advantages, a significant challenge remains in securely managing sensitive data as it flows through the network of ephemeral function executions in serverless computing environments within untrusted clouds. While Confidential Virtual Machines (CVMs) offer a promising secure execution environment, their integration with serverless architectures currently faces fundamental limitations in key areas: security, performance, and resource efficiency. We present WALLET, a confidential computing system for secure serverless deployments to overcome these limitations. By employing nested confidential execution and a decoupled guest OS within CVMs, WALLET runs each function in a minimal "trustlet", significantly improving security through a reduced Trusted Computing Base (TCB). Furthermore, by leveraging a data-centric I/O architecture built upon a lightweight LibOS, WALLET optimizes network communication to address performance and resource efficiency challenges. Our evaluation shows that compared to CVM-based deployments, WALLET has 4.3x smaller TCB, improves end-to-end latency (15-93%), achieves higher function density (up to 907x), and reduces inter-function communication (up to 27x) and function chaining latency (16.7-30.2x); thus, WALLET offers a practical system for confidential serverless computing.

cs.CR↗

CaMDN: Enhancing Cache Efficiency for Multi-tenant DNNs on Integrated NPUs

With the rapid development of DNN applications, multi-tenant execution, where multiple DNNs are co-located on a single SoC, is becoming a prevailing trend. Although many methods are proposed in prior works to improve multi-tenant performance, the impact of shared cache is not well studied. This paper proposes CaMDN, an architecture-scheduling co-design to enhance cache efficiency for multi-tenant DNNs on integrated NPUs. Specifically, a lightweight architecture is proposed to support model-exclusive, NPU-controlled regions inside shared cache to eliminate unexpected cache contention. Moreover, a cache scheduling method is proposed to improve shared cache utilization. In particular, it includes a cache-aware mapping method for adaptability to the varying available cache capacity and a dynamic allocation algorithm to adjust the usage among co-located DNNs at runtime. Compared to prior works, CaMDN reduces the memory access by 33.4% on average and achieves a model speedup of up to 2.56$\times$ (1.88$\times$ on average).

cs.AR↗

RTOS Architectures that Solve the Diminishing Bandwidth Problem (with Multi-core Support)

The Diminishing Bandwidth Problem is a long stand-ing, previously unidentified, extensibility problem of current real-time operating systems characterized by a superficial dependency between the number of tasks in a system and the maximum bandwidth associated with an unrelated peripheral device. In the worst case, this diabolical deficiency will continue to decrease the maximum bandwidth of a peripheral device as more tasks are added to the application. If this is not taken into account, a previously functional application may experience data loss if more tasks are added to it in order to, for example, implement new features. Three novel RTOS architectures that solve the Diminishing Bandwidth Problem are specified and discussed: the Defer Structure RTOS Architecture, the Barriers and Requests RTOS Architecture, and the Strictly Atomic RTOS Architecture. Finally, two hardware solutions to the Diminishing Bandwidth Problem are also presented.

cs.OS↗

Harmonia: End-to-End RAG Serving Optimization

Retrieval-Augmented Generation (RAG) improves the reliability of large language models by integrating external knowledge, but serving RAG pipelines efficiently is challenging because requests traverse heterogeneous components spanning LLM inference, databases, and CPU-side processing. We present Harmonia, an end-to-end RAG serving framework that addresses these bottlenecks through (i) a flexible pipeline specification interface for composing custom workflows, (ii) heterogeneity-aware deployment that provisions and configures components as a distributed inference system, and (iii) a closed-loop runtime controller that monitors load and execution progress and reduces SLO violations through request prioritization and auto-scaling. Across four RAG applications, Harmonia outperforms commercial alternatives, improving throughput by more than 2.04x while reducing SLO violations by up to 78.4 percent.

cs.DC↗

Adaptive Migration Decision for Multi-Tenant Memory Systems

Tiered memory systems consisting of fast small memory and slow large memory have emerged to provide high capacity memory in a cost-effective way. The effectiveness of tiered memory systems relies on how many memory accesses can be absorbed by the fast first-tier memory by page migration. The recent studies proposed several different ways of detecting hot pages and migrating them efficiently. However, our investigation shows that page migration is not always beneficial as it has the associated cost of detecting and migrating hot pages. When an application is unfriendly to migration, it is often better not to migrate pages at all. Based on the observation on migration friendliness, this paper proposes a migration control framework for multi-tenant tiered memory systems. First, it proposes a detection mechanism for migration friendliness, using per-page ping-pong status. Ping-pong pages which are promoted and demoted repeatedly in a short period of time tells migration effectiveness. Based on their change behaviors, migration is stopped or continued. After the page migration is stopped, the second mechanism detects changes of memory access patterns in a low cost way to determine whether migration needs to be resumed. Finally, as each application has a different behavior, our framework provides per-process migration control to selectively stop and start migration depending on application characteristics. We implement the framework in the Linux kernel. The evaluation with a commercial CXL-based tiered memory system shows that it effectively controls migration in single and multi-tenant environments.

cs.OS↗

Enabling Syscall Intercept for RISC-V

The European Union technological sovereignty strategy centers around the RISC-V Instruction Set Architecture, with the European Processor Initiative leading efforts to build production-ready processors. Focusing on realizing a functional RISC-V ecosystem, the BZL initiative (www.bzl.es) is making an effort to create a software stack along with the hardware. In this work, we detail the efforts made in porting a widely used syscall interception library, mainly used on AdHocFS (i.e., DAOS, GekkoFS), to RISC-V and how we overcame some of the limitations encountered.

cs.OS↗

Testing Access-Control Configuration Changes for Web Applications

Access-control misconfigurations are among the main causes of today's data breaches in web applications. However, few techniques are available to support automatic and systematic testing for access-control changes and detecting risky changes to prevent severe consequences. As a result, those critical security configurations often lack testing, or are tested manually in an ad hoc way. This paper advocates that tests should be made available for users to test access-control configuration changes. The key challenges are such tests need to be run with production environments (to reason end-to-end behavior) and need to be performance-efficient. We present a new approach to create such tests, as a mini test environment incorporating production program and data, called ACtests. ACtests report the impacts of access-control changes, namely the requests that were denied but would be allowed after a change, and vice versa. Users can validate if the changed requests are intended or not and identify potential security vulnerabilities. We evaluate ACtests with 193 public configurations of widely-used web applications on Dockerhub. ACtests detect 168 new vulnerabilities from 72 configuration images. We report them to the image maintainers: 54 of them have been confirmed and 44 have been fixed. We also conduct in-depth experiments with five real-world deployed systems, including Wikipedia and a commercial company's web proxy. Our results show that ACtests effectively and efficiently detect all the change impacts.

cs.CR↗

KernelOracle: Predicting the Linux Scheduler's Next Move with Deep Learning

Efficient task scheduling is paramount in the Linux kernel, where the Completely Fair Scheduler (CFS) meticulously manages CPU resources to balance high utilization with interactive responsiveness. This research pioneers the use of deep learning techniques to predict the sequence of tasks selected by CFS, aiming to evaluate the feasibility of a more generalized and potentially more adaptive task scheduler for diverse workloads. Our core contributions are twofold: first, the systematic generation and curation of a novel scheduling dataset from a running Linux kernel, capturing real-world CFS behavior; and second, the development, training, and evaluation of a Long Short-Term Memory (LSTM) network designed to accurately forecast the next task to be scheduled. This paper further discusses the practical pathways and implications of integrating such a predictive model into the kernel's scheduling framework. The findings and methodologies presented herein open avenues for data-driven advancements in kernel scheduling, with the full source code provided for reproducibility and further exploration.

cs.LG↗

LiteCUA: Computer as MCP Server for Computer-Use Agent on AIOS

We present AIOS 1.0, a novel platform designed to advance computer-use agent (CUA) capabilities through environmental contextualization. While existing approaches primarily focus on building more powerful agent frameworks or enhancing agent models, we identify a fundamental limitation: the semantic disconnect between how language models understand the world and how computer interfaces are structured. AIOS 1.0 addresses this challenge by transforming computers into contextual environments that language models can natively comprehend, implementing a Model Context Protocol (MCP) server architecture to abstract computer states and actions. This approach effectively decouples interface complexity from decision complexity, enabling agents to reason more effectively about computing environments. To demonstrate our platform's effectiveness, we introduce LiteCUA, a lightweight computer-use agent built on AIOS 1.0 that achieves a 14.66% success rate on the OSWorld benchmark, outperforming several specialized agent frameworks despite its simple architecture. Our results suggest that contextualizing computer environments for language models represents a promising direction for developing more capable computer-use agents and advancing toward AI that can interact with digital systems.

cs.AI↗

Lazarus Group Targets Crypto-Wallets and Financial Data while employing new Tradecrafts

This report presents a comprehensive analysis of a malicious software sample, detailing its architecture, behavioral characteristics, and underlying intent. Through static and dynamic examination, the malware core functionalities, including persistence mechanisms, command-and-control communication, and data exfiltration routines, are identified and its supporting infrastructure is mapped. By correlating observed indicators of compromise with known techniques, tactics, and procedures, this analysis situates the sample within the broader context of contemporary threat campaigns and infers the capabilities and motivations of its likely threat actor. Building on these findings, actionable threat intelligence is provided to support proactive defenses. Threat hunting teams receive precise detection hypotheses for uncovering latent adversarial presence, while monitoring systems can refine alert logic to detect anomalous activity in real time. Finally, the report discusses how this structured intelligence enhances predictive risk assessments, informs vulnerability prioritization, and strengthens organizational resilience against advanced persistent threats. By integrating detailed technical insights with strategic threat landscape mapping, this malware analysis report not only reconstructs past adversary actions but also establishes a robust foundation for anticipating and mitigating future attacks.

cs.CR↗

Learning Semantics, Not Addresses: Runtime Neural Prefetching for Far Memory

Memory prefetching has long boosted CPU caches and is increasingly vital for far-memory systems, where large portions of memory are offloaded to cheaper, remote tiers. While effective prefetching requires accurate prediction of future accesses, prior ML approaches have been limited to simulation or small-scale hardware. We introduce FarSight, the first Linux-based far-memory system to leverage deep learning by decoupling application semantics from runtime memory layout. This separation enables offline-trained models to predict access patterns over a compact ordinal vocabulary, which are resolved at runtime through lightweight mappings. Across four data-intensive workloads, FarSight delivers up to 3.6x higher performance than the state-of-the-art.

cs.LG↗

Söze: One Network Telemetry Is All You Need for Per-flow Weighted Bandwidth Allocation at Scale

Weighted bandwidth allocation is a powerful abstraction that has a wide range of use cases in modern data center networks. However, realizing highly agile and precise weighted bandwidth allocation for large-scale cloud environments is fundamentally challenging. In this paper, we propose Söze, a lightweight decentralized weighted bandwidth allocation system that leverages simple network telemetry features of commodity Ethernet switches. Given the flow weights, Söze can effectively use the telemetry information to compute and enforce the weighted bandwidth allocations without per-flow, topology, or routing knowledge. We demonstrate the effectiveness of Söze through simulations and testbed experiments, improving TPC-H jobs completion time by up to $0.59\times$ and $0.79\times$ on average.

cs.NI↗

Asterinas: A Linux ABI-Compatible, Rust-Based Framekernel OS with a Small and Sound TCB

How can one build a feature-rich, general-purpose, Rust-based operating system (OS) with a minimal and sound Trusted Computing Base (TCB) for memory safety? Existing Rust-based OSes fall short due to their improper use of unsafe Rust in kernel development. To address this challenge, we propose a novel OS architecture called framekernel that realizes Rust's full potential to achieve intra-kernel privilege separation, ensuring TCB minimality and soundness. We present OSTD, a streamlined framework for safe Rust OS development, and Asterinas, a Linux ABI-compatible framekernel OS implemented entirely in safe Rust using OSTD. Supporting over 210 Linux system calls, Asterinas delivers performance on par with Linux, while maintaining a minimized, memory-safety TCB of only about 14.0% of the codebase. These results underscore the practicality and benefits of the framekernel architecture in building safe and efficient OSes.

cs.OS↗

Efficient Memory Tiering in a Virtual Machine

Memory tiering is the norm to effectively tackle the increasing server memory total cost of ownership (TCO) and the growing data demands of modern data center workloads. However, the host-based state-of-the-art memory tiering solutions can be inefficient for a virtualized environment when (i) the frequently accessed data are scattered across the guest physical address space or (ii) the accesses to a huge page inside the guest are skewed due to a small number of subpages being hot. Scattered or skewed accesses make the whole huge page look hot in the host address space. This results in host selecting and placing sparsely accessed huge pages in near memory, wasting costly near memory resources. We propose a host-agnostic technique employed inside the guest that exploits the two-level address translation in a virtualized environment to consolidate the scattered and skewed accesses to a set of guest physical address ranges. Consolidation transforms sparsely hot huge pages to densely hot huge pages in the host address space context. As a consequence, host-based tiering solutions can place densely hot huge pages in near memory, improving near memory utilization. Our evaluation of our technique on standalone real-world benchmarks with state-of-the-art host-based tiering show 50-70% reduction in near memory consumption at similar performance levels, while evaluation at scale improves performance by 10-13% with similar memory TCO.

cs.OS↗

EROICA: Online Performance Troubleshooting for Large-scale Model Training

Troubleshooting performance problems of large model training (LMT) is immensely challenging, due to unprecedented scales of modern GPU clusters, the complexity of software-hardware interactions, and the data intensity of the training process. Existing troubleshooting approaches designed for traditional distributed systems or datacenter networks fall short and can hardly apply to real-world training systems. In this paper, we present EROICA, the first online troubleshooting system that provides both fine-grained observation based on profiling, and coverage of all machines in GPU clusters, to diagnose performance issues in production, including both hardware and software problems (or the mixture of both). EROICA effectively summarizes runtime behavior patterns of LMT function executions via online profiling, and leverages differential observability to localize the root cause with minimal production impact. EROICA has been deployed as a production service for large-scale GPU clusters of ~100,000 GPUs for 1.5 years. It has diagnosed a variety of difficult performance issues with 97.5% success.

cs.DC↗

On the Impossibility of a Perfect Hypervisor

We establish a fundamental impossibility result for a `perfect hypervisor', one that (1) preserves every observable behavior of any program exactly as on bare metal and (2) adds zero timing or resource overhead. Within this model we prove two theorems. (1) Indetectability Theorem. If such a hypervisor existed, no guest-level program, measurement, or timing test could distinguish it from native execution; all traces, outputs, and timings would be identical. (2) Impossibility Theorem. Despite that theoretical indetectability, a perfect hypervisor cannot exist on any machine with finite computational resources. These results are architecture-agnostic and extend beyond hypervisors to any virtualization layer emulators, sandboxes, containers, or runtime-instrumentation frameworks. Together they provide a formal foundation for future work on the principles and limits of virtualization.

cs.OS↗

Playing in the Sandbox: A Study on the Usability of Seccomp

Sandboxing restricts what applications do, and prevents exploited processes being abused; yet relatively few applications get sandboxed: why? We report a usability trial with 7 experienced Seccomp developers exploring how they approached sandboxing an application and the difficulties they faced. The developers each approached sandboxing the application differently and each came to different solutions. We highlight many challenges of using Seccomp, the sandboxing designs by the participants, and what developers think would make it easier for them to sandbox applications effectively.

cs.OS↗

Semantic Scheduling for LLM Inference

Conventional operating system scheduling algorithms are largely content-ignorant, making decisions based on factors such as latency or fairness without considering the actual intents or semantics of processes. Consequently, these algorithms often do not prioritize tasks that require urgent attention or carry higher importance, such as in emergency management scenarios. However, recent advances in language models enable semantic analysis of processes, allowing for more intelligent and context-aware scheduling decisions. In this paper, we introduce the concept of semantic scheduling in scheduling of requests from large language models (LLM), where the semantics of the process guide the scheduling priorities. We present a novel scheduling algorithm with optimal time complexity, designed to minimize the overall waiting time in LLM-based prompt scheduling. To illustrate its effectiveness, we present a medical emergency management application, underscoring the potential benefits of semantic scheduling for critical, time-sensitive tasks. The code and data are available at https://github.com/Wenyueh/latency_optimization_with_priority_constraints.

cs.LG↗