🤖 AI Summary
To address high data movement overhead, severe memory fragmentation, and insufficient hardware-software co-design in multi-terabyte OLAP query processing under GPU acceleration, this paper proposes a distributed GPU-accelerated query processing framework. Our method introduces a dedicated asynchronous control mechanism that tightly couples GPU computation, network communication, multi-level storage spilling, and data prefetching; it also employs a fixed-page host memory locking allocation strategy to optimize cross-layer data transfer and memory utilization. Evaluation on cloud-based TPC-H benchmarks (scale factors 1K–30K) shows our framework achieves up to 4× higher performance than Databricks Photon. Moreover, it completes full-scale TPC-H and TPC-DS queries on 100 TB datasets using only two NVIDIA DGX A100 nodes—demonstrating substantial throughput improvement and significant reduction in query execution cost.
📝 Abstract
Online analytical processing of queries on datasets in the many-terabyte range is only possible with costly distributed computing systems. To decrease the cost and increase the throughput, systems can leverage accelerators such as GPUs, which are now ubiquitous in the compute infrastructure. This introduces many challenges, the majority of which are related to when, where, and how to best move data around the system. We present Theseus -- a production-ready enterprise-scale distributed accelerator-native query engine designed to balance data movement, memory utilization, and computation in an accelerator-based system context. Specialized asynchronous control mechanisms are tightly coupled to the hardware resources for the purpose of network communication, data pre-loading, data spilling across memories and storage, and GPU compute tasks. The memory subsystem contains a mechanism for fixed-size page-locked host memory allocations to increase throughput and reduce memory fragmentation. For the TPC-H benchmarks at scale factors ranging from 1k to 30k on cloud infrastructure, Theseus outperforms Databricks Photon by up to $4 imes$ at cost parity. Theseus is capable of processing all queries of the TPC-H and TPC-DS benchmarks at scale factor 100k (100 TB scale) with as few as 2 DGX A100 640GB nodes.