ucTrace: A Multi-Layer Profiling Tool for UCX-driven Communication

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Gencer, Emir, Issa, Mohammad Kefah Taha, Turimbetov, Ilyas, Trotter, James D., Unat, Didem
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866914342325190656
author Gencer, Emir
Issa, Mohammad Kefah Taha
Turimbetov, Ilyas
Trotter, James D.
Unat, Didem
author_facet Gencer, Emir
Issa, Mohammad Kefah Taha
Turimbetov, Ilyas
Trotter, James D.
Unat, Didem
contents UCX is a communication framework that enables low-latency, high-bandwidth communication in HPC systems. With its unified API, UCX facilitates efficient data transfers across multi-node CPU-GPU clusters. UCX is widely used as the transport layer for MPI, particularly in GPU-aware implementations. However, existing profiling tools lack fine-grained communication traces at the UCX level, do not capture transport-layer behavior, or are limited to specific MPI implementations. To address these gaps, we introduce ucTrace, a novel profiler that exposes and visualizes UCX-driven communication in HPC environments. ucTrace provides insights into MPI workflows by profiling message passing at the UCX level, linking operations between hosts and devices (e.g., GPUs and NICs) directly to their originating MPI functions. Through interactive visualizations of process- and device-specific interactions, ucTrace helps system administrators, library and application developers optimize performance and debug communication patterns in large-scale workloads. We demonstrate ucTrace's features through a wide range of experiments including MPI point-to-point behavior under different UCX settings, Allreduce comparisons across MPI libraries, communication analysis of a linear solver, NUMA binding effects, and profiling of GROMACS MD simulations with GPU acceleration at scale. ucTrace is publicly available at https://github.com/ParCoreLab/ucTrace.
format Preprint
id arxiv_https___arxiv_org_abs_2602_19084
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle ucTrace: A Multi-Layer Profiling Tool for UCX-driven Communication
Gencer, Emir
Issa, Mohammad Kefah Taha
Turimbetov, Ilyas
Trotter, James D.
Unat, Didem
Distributed, Parallel, and Cluster Computing
UCX is a communication framework that enables low-latency, high-bandwidth communication in HPC systems. With its unified API, UCX facilitates efficient data transfers across multi-node CPU-GPU clusters. UCX is widely used as the transport layer for MPI, particularly in GPU-aware implementations. However, existing profiling tools lack fine-grained communication traces at the UCX level, do not capture transport-layer behavior, or are limited to specific MPI implementations. To address these gaps, we introduce ucTrace, a novel profiler that exposes and visualizes UCX-driven communication in HPC environments. ucTrace provides insights into MPI workflows by profiling message passing at the UCX level, linking operations between hosts and devices (e.g., GPUs and NICs) directly to their originating MPI functions. Through interactive visualizations of process- and device-specific interactions, ucTrace helps system administrators, library and application developers optimize performance and debug communication patterns in large-scale workloads. We demonstrate ucTrace's features through a wide range of experiments including MPI point-to-point behavior under different UCX settings, Allreduce comparisons across MPI libraries, communication analysis of a linear solver, NUMA binding effects, and profiling of GROMACS MD simulations with GPU acceleration at scale. ucTrace is publicly available at https://github.com/ParCoreLab/ucTrace.
title ucTrace: A Multi-Layer Profiling Tool for UCX-driven Communication
topic Distributed, Parallel, and Cluster Computing
url https://arxiv.org/abs/2602.19084