Helen Xu

Helen Xu

Office: MIT CSAIL, 32-G770.
Email: hjxu at mit dot edu
Online presence: Google Scholar and Linkedin.
ORCID iD iconorcid.org/0000-0003-2232-3305

About me

I am a PhD student in the Supertech group at MIT and am fortunate to be advised by Charles Leiserson.
I graduated with a BS in Computer Science and Applied Math at Stony Brook University, where I was lucky to have the opportunity to work with Michael Bender and Rob Johnson.
I finished my SM at MIT in 2018. My thesis "Fill Estimation for Blocked Sparse Matrices and Tensors" can be found here.
I spent Summer 2019 at Microsoft Research in Cambridge, UK with Dr. Nuno Lopes.
I visited ENS Lyon from January to March 2020 under a Chateubriand Fellowship.
I spent Summer 2020 at NVIDIA Research working with Michael Pellauer.
My research interests include parallel computing, cache-efficient algorithms, and performance engineering.


  1. Terrace: A Hierarchical Graph Container for Skewed Dynamic Graphs
    with Prashant Pandey, Brian Wheatman, and Aydin Buluc
          SIGMOD 21 [pdf] [code]

  2. A Parallel Packed Memory Array to Store Dynamic Graphs
    with Brian Wheatman
          ALENEX 21 [pdf] [SIAM]

  3. *Beyond Worst-case Analysis of Multicore Caching Strategies
    with Shahin Kamali
          APOCS 21 [arXiv]

  4. Work-Efficient Parallel Algorithms for Accurate Floating-Point Prefix Sums
    with Sean Fraser and Charles E. Leiserson
          HPEC 20 [pdf]

  5. *Brief Announcement: Multicore Paging Algorithms Cannot Be Competitive
    with Shahin Kamali
          SPAA 20 [ACM]

  6. *Closing the Gap Between Cache-oblivious and Cache-adaptive Analysis
    with Michael A. Bender, Rezaul A. Chowdhury, Rathish Das, Rob Johnson, William Kuszmaul, Andrea Lincoln, Quanquan C. Liu, and Jayson Lynch
          SPAA 20 [ACM]

  7. *Dynamic Programming with Spiking Neural Computing
    with James Aimone, Ojas Parekh, Cynthia Phllips, Ali Pinar, and William Severa
          ICONS 19 [pdf] [ACM]

  8. Packed Compressed Sparse Row: A Dynamic Graph Representation
    with Brian Wheatman
          HPEC 18 [pdf]

  9. *Cache-Adaptive Exploration: Experimental Results and Scan-Hiding for Adaptivity
    with Andrea Lincoln, Quanquan C. Liu, and Jayson Lynch
          SPAA 18 [pdf] [ACM]

  10. A Fill Estimation Algorithm for Sparse Matrices and Tensors in Blocked Formats
    with Peter Ahrens and Nicholas Schiefer
          IPDPS 18 [pdf]

  11. *Write-Optimized Skip Lists
    with Michael A. Bender, Martin Farach-Colton, Rob Johnson, Simon Mauras, Tyler Mayer, and Cynthia Phillips
          PODS 17 [pdf] [ACM]
  12. * denotes author lists in alphabetical order.


Performance Engineering of Software Systems (MIT 6.172, Fall 2017 and Fall 2018).
Foundations of Computer Science (SBU CSE 215, Spring 2016).
Foundations of Computer Science: Honors (SBU CSE 150, Fall 2015).
Applied Linear Algebra (SBU AMS 210, Fall 2013).


In Spring 2018, I joined the EECS Communication Lab.
I blog for the MIT graduate admissions blog. You can find more information about our standup class here.
In 2017, I served as president of Graduate Women of Course 6 (GW6).