Scalable Memory Safety for Concurrent Data Structures via Hardware-Software Codesign

Title of the Talk: Scalable Memory Safety for Concurrent Data Structures via Hardware-Software Codesign
Speakers: Ajay Singh
Host Faculty: Prof.Sathya Peri
Date: Sep 19, 2025
Time: 2:30 pm
Venue: CS - LH-1, EE/CS building

Abstract:
Concurrent reclamation algorithms address use-after-free races in concurrent data structures to provide memory safety. However, these algorithms are often designed based on simplified theoretical models and fail to consider the broader system context in which they operate. For example, they overlook how memory locations are managed or synchronized at lower system layers, such as memory allocators and the cache subsystem. This isolated approach misses opportunities to leverage events occurring at these lower layers, which could solve the same problem more efficiently.

In this talk I will present a hardware-software co-design approach to address concurrent memory reclamation in concurrent data structures. The synchronization needed for concurrent memory reclamation already occurs at the cache level through coherence protocol messages. Therefore, instead of duplicating this mechanism at the application level, we can harness these cache-level messages and expose them to programmers, offering a more efficient solution. More details of the work appear in IPDPS 2023 paper titled: “Efficient Hardware Primitives for Immediate Memory Reclamation in Optimistic Data Structures”.

Bio:
Ajay Singh completed his PhD from the University of Waterloo and currently is a visiting researcher at ICS Forth. His research is inherently interdisciplinary, integrating multiple subfields within computer science—including Data Structures & Algorithms, Computer Architecture, Programming Languages, Operating Systems, and Networks—with a focus on parallelism, concurrency, and distribution.

He is a recipient of the Distinguished Paper Award at PPoPP 2025, the Best Artefact Award at PPoPP 21, the David R Cheriton Graduate Scholarship (valued 10K CAD, awarded to top graduate students of the department) 2022, the Charpak Research Scholarship 2017 for master’s internship at INRIA Lab in France. He has also worked as software engineer at Samsung Research Institute where he contributed to Samsung Feature Phones like Samsung Guru, Metro and FM plus series.