[CS] Ivy Wang Candidacy Exam/Jun 6, 2025

[via cs]

This is an announcement of Ivy Wang's Candidacy Exam.
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Candidate: Ivy Wang

Date: Friday, June 06, 2025

Time: 10 am CST

Remote Location: https://uchicago.zoom.us/j/93576942595?pwd=28LvHtXdh17brHNPapA5jRwUrnGA7b.1&from=addon

Location: JCL 354

Title: UDTrans: Scalable Address Translation for Petabytes of Global Memory 

Abstract: Virtual memory on a global address space simplifies memory management for programmers: page-based translation is deployed in all major modern computer systems. As application data sizes continue to increase, terabyte datasets are commonplace, and those with many petabytes are increasingly available. However, increasing data makes address translation a significant overhead. As a result, address translation is an increasingly critical bottleneck as TLB reach cannot cover application memory footprints. For example, Translation overhead can exceed > 100% due to TLB misses and resulting page walks for today’s CPU and GPU
systems.

An ideal address translation theme for a massively parallel system with distributed memory should achieve low overhead address translation and support customization of the data layout to distribute the data across the system.

 We propose a novel translation scheme, UDTrans, that provides compact, efficient translation. Each translation controls access to a segment of arbitrary size and provides a user-controlled data layout across distributed memories. These attributes provide scalable, efficient translation to applications with petabyte datasets. Furthermore, the data layout customization allows applications to control data locality. We evaluate the proposed scheme to the traditional page-based scheme and the segment-based scheme and show that UDTrans is able to achieve both performance and data locality at the scale with magnitudes less overhead compared to conventional page-based scheme.

Advisors: Andrew Chien

Committee Members: Andrew Chien, Ian Foster, and Haryadi Gunawi