Query optimization is critical in relational database management systems (DBMSs) for ensuring efficient query processing. The query optimizer relies on precise selectivity and cost estimates to generate optimal query plans for execution. However, this static query optimization approach falls short for DBMSs handling machine learning (ML) queries. ML-centric DBMSs face distinct challenges in query optimization. First, performance bottlenecks shift to user-defined functions (UDFs), often encapsulating deep learning models, making it difficult to estimate UDF statistics without profiling the query. Second, optimal query plans for ML queries are data-dependent, requiring dynamic plan adjustments during execution. To address these challenges, we introduce Aero, an ML-centric DBMS that utilizes adaptive query processing (AQP) for efficiently processing ML queries. Aero optimizes the evaluation of UDF-based query predicates by dynamically adjusting predicate evaluation order and enhancing UDF execution scalability. By integrating AQP, Aero continuously monitors UDF statistics, routes data to predicates in an optimal order, and dynamically allocates resources for evaluating predicates. Aero achieves up to 6.4x speedup compared to a state-of-the-art ML-centric DBMS across four diverse use cases, with no impact on accuracy.

User-defined functions (UDFs) extend the capabilities of SQL by improving code reusability and encapsulating complex logic, but can hinder the performance due to optimization and execution inefficiencies. Prior approaches attempt to address this by rewriting UDFs into native SQL, which is then inlined into the SQL queries that invoke them. However, these approaches are either limited to simple pattern matching or require the synthesis of complex verification conditions from procedural code, a process that is brittle and difficult to automate. This limits coverage and makes the translation approaches less extensible to previously unseen procedural constructs. In this work, we present QURE, a framework that (1) leverages large language models (LLMs) to translate UDFs to native SQL, and (2) introduces a novel formal verification method to establish equivalence between the UDF and its translation. QURE uses the semantics of SQL operators to automate the derivation of verification conditions, in turn resulting in broad coverage and high extensibility. We model a large set of imperative constructs, particularly those common in Python and Pandas UDFs, in an intermediate verification language, allowing for the verification of their SQL translation. In our empirical evaluation of Python and Pandas UDFs, equivalence is successfully verified for 88% of UDF-SQL pairs (the rest lack semantically-equivalent SQLs) and LLMs correctly translate 84% of the UDFs. Executing the translated UDFs achieves median performance improvements of 23x on single-node clusters and 12x on 12-node clusters compared to the original UDFs, while also significantly reducing out-of-memory errors.

Deep neural networks have produced tremendous advancements in super-resolution (SR) results. These improvements often come at the cost of inference latency, which is particularly important in low-resource devices. This paper therefore proposes a novel method to optimize the inference latency of SR models, called EHT-SR (Entropy-Based Hybrid Tiled SR), which leverages both accurate but slow DNN-based methods and a simple but fast bicubic interpolation for super-resolution. Particularly, we observe that a lightweight bicubic interpolation can still provide good image super-resolution quality for selected regions of the input image. An entropy-based heuristic, which we derive from a rigorous analysis of the bicubic interpolation, allows to select the best tiles in the input image that can be super-resolved using bicubic interpolation, while the remaining tiles are processed using a DNN-based SR method. This approach allows us to consistently speed-up the SR inference latency with only minimal degradation in image quality. Extensive evaluation results with different SR baselines and datasets show how our EHT-SR approach can speed-up inference by up to 27% and 39% on GPU and CPU platforms, respectively, without negatively impacting the quality of the super-resolved content.

GPUs offer massive parallelism and high-bandwidth memory access, making them an attractive option for accelerating data analytics in database systems. However, while modern GPUs possess more resources than ever before (e.g., higher DRAM bandwidth), efficient system implementations and judicious resource allocations for query processing are still necessary for optimal performance. Database systems can save GPU runtime costs through just-enough resource allocation or improve query throughput with concurrent query processing by leveraging new GPU resource-allocation capabilities, such as Multi-Instance GPU (MIG). In this paper, we do a cross-stack performance and resource-utilization analysis of four GPU database systems, including Crystal (the state-of-the-art GPU database, performance-wise) and TQP (the latest entry in the GPU database space). We evaluate the bottlenecks of each system through an in-depth microarchitectural study and identify resource underutilization by leveraging the classic roofline model. Based on the insights gained from our investigation, we propose optimizations for both system implementation and resource allocation, using which we are able to achieve 1.9x lower latency for single-query execution and up to 6.5x throughput improvement for concurrent query execution.

In this demonstration, we will present EVA, an end-to-end AI-Relational database management system. We will demonstrate the capabilities and utility of EVA using three usage scenarios: (1) EVA serves as a backend for an exploratory video analytics interface developed using Streamlit and React, (2) EVA seamlessly integrates with the Python and Data Science ecosystems by allowing users to access EVA in a Python notebook alongside other popular libraries such as Pandas and Matplotlib, and (3) EVA facilitates bulk labeling with Label Studio, a widely-used labeling framework. By optimizing complex vision queries, we illustrate how EVA allows a wide range of application developers to harness the recent advances in computer vision.

Graphics processing units (GPUs) have become essential general-purpose computing platforms to accelerate a wide range of workloads, such as deep learning, scientific, and high-performance computing (HPC) applications. However, recent memory corruption attacks, such as buffer overflow, exposed security vulnerabilities in GPUs. We demonstrate that out-of-bounds writes are reproducible on an Nvidia GPU, which can enable other security attacks.

Video database management systems (VDBMSs) enable automated analysis of videos at scale using computationally-intensive deep learning models. To reduce the computational overhead of these models, researchers have proposed two techniques: (1) leveraging a specialized, lightweight model to filter out irrelevant frames or to directly answer the query, and (2) using a cascade of models of increasing complexity to answer the query. For both techniques, the query optimizer generates a coarse-grained query plan for the entire video. These techniques suffer from four limitations: (1) lower query accuracy over hard-to-detect predicates, (2) lower filtering efficacy with frequently-occurring objects, (3) lower accuracy due to nontrivial model cascade configuration, and (4) missed optimization opportunities due to coarse-grained planning for the entire video.

Memory-bound sparse gathering, caused by irregular random memory accesses, has become an obstacle in several on-demand applications such as embedding lookup in recommendation systems. To reduce the amount of data movement, and thereby better utilize memory bandwidth, previous studies have proposed near-data processing (NDP) solutions. The issue of prior work, however, is that they either minimize data movement effectively at the cost of limited memory parallelism or try to improve memory parallelism (up to a certain degree) but cannot successfully decrease data movement, as prior proposals rely on spatial locality (an optimistic assumption) to utilize NDP. More importantly, neither approach proposes a solution for gathering data from random memory addresses; rather they just offload operations to NDP. We propose an effective solution for sparse gathering, an efficient near-memory intelligent reduction (Fafnir) tree, the leaves of which are all the ranks in a memory system, and the nodes gradually apply reduction operations while data is gathered from any rank. By using such an overall tree, Fafnir does not rely on spatial locality; therefore, it minimizes data movement by performing entire operations at NDP and fully benefits from parallel memory accesses in parallel processing at NDP. Further, Fafnir offers other advantages such as using fewer connections (because of the tree topology), eliminating redundant memory accesses without using costly and less effective caching mechanisms, and being applicable to other domains of sparse problems such as scientific computing and graph analytics. To evaluate Fafnir, we implement it on an XCVU9P Xilinx FPGA and in 7 nm ASAP ASIC. Fafnir looks up the embedding tables up to 21.3× more quickly than the state-of-the-art NDP proposal. Furthermore, the generic architecture of Fafnir allows running classic sparse problems using the same 1.2 mm2hardware up to 4.6× more quickly than the state of the art.

Recent advancements in deep neural networks (DNNs) have enabled us to solve traditionally challenging problems. To deploy a service based on DNNs, since DNNs are compute intensive, consumers need to rely on compute resources in the cloud. This approach, in addition to creating a dependency on the high-quality network infrastructure and data centers, raises new privacy concerns because of the sharing of private data. These concerns and challenges limit the widespread use of DNN-based applications, so many researchers and companies are trying to optimize DNNs for fast in-the-edge execution. Executing DNNs is further pushed to the edge with the widespread use of embedded processors and ubiquitous wireless networks in Internet-of-Things (IoT) devices. However, inadequate power and computing resources of edge devices, along with the small number of local requests, limit the use of prevalent optimization techniques such as batch processing. In this article, we enable the utilization of the aggregated computing power of several IoT devices by creating a local collaborative network for a subset of DNNs, visual-based applications. In this approach, IoT devices cooperate to conduct single-batch inferencing in real time while exploiting several new model-parallelism methods, which will be introduced in this article. Our approach enhances the collaborative system by creating a balanced and distributed processing pipeline while adjusting the tasks in real time. For experiments, we deploy a system with up to 10 Raspberry Pis and execute state-of-the-art visual models, such as AlexNet, VGG16, Xception, and C3D.

Internet of Things (IoT) devices have access to an abundance of raw data for processing. With deep neural networks (DNNs), not only the demand for the computing power of IoT devices is increasing, but also privacy concerns are motivating the importance of close-to-edge computation. DNN execution by distributing its computation is common in IoT systems. However, managing unstable latencies in a network and intermittent failures are serious challenges. Our work provides robustness and close-to-zero recovery latency by adapting coded distributed computing (CDC). We analyze robust execution on a mesh of Raspberry Pis by studying four DNNs.

Deep neural networks (DNNs) have seen resurgent attraction to be implemented in edge applications. However, such implementations are not easy to achieve because execution of DNNs often require more resources than those provided by individual edge devices. On the other hand, relying on model-level distribution methods to implement a DNN on connected edge devices leads to costly communication overheads. To utilize available in-the-edge resources with less communication overhead, we propose using edge-tailored models comprised of nearly-independent narrow DNNs, the inference of which are accelerated using small cost-efficient RISC-based engines. We implement these engines on PYNQ boards as a platform that mimics the limited resources of edge devices. We create the narrow DNNs based on the available resources of PYNQ boards, and allocate each narrow DNN to one engine, implemented in an FPGA. We compare the communication overhead of our implantation against the state-of-the-art model-level distribution methods.