Research

Best Paper FAST '20 - CAD
UW CS Graduate Student Research (Best Dissertation Research) Award - Honorable Mention - 2019
Best Paper FAST '18 - PAR/CTRL
Best Paper FAST '17 - CCFS
Best Paper Nominee FAST '17- Redundancy Does Not Imply Fault Tolerance

Teaching

List of Teachers Ranked as Excellent at UIUC (for CS598 - Storage Systems Fall 2022)
CS 739 ranked 1st among all Spring 20 courses in student evaluations
Nominated for SACM CoW Teaching Award for CS 739

Service

Distinguished Reviewer HotStorage - 2021
Best Shadow PC Reviewer Eurosys '19

Grants and Scholarships

MS Azure Credits Research Award for $50,000 - 2019
Facebook Distributed Systems Research Award for $50,000 - 2019
Alumni Scholarship, UW Madison - 2013

SplitFT: Fault Tolerance for Disaggregated Datacenters via Remote Memory Logging
Xuhao Luo, Ramnatthan Alagappan, Aishwarya Ganesan
(To Appear) EuroSys 2024
PDF

Automatic Reliability Testing For Cluster Management Controllers
Xudong Sun, Wenqing Luo, Tyler Gu, Aishwarya Ganesan, Ramnatthan Alagappan, Michael Gasch, Lalith Suresh, and Tianyin Xu
16th USENIX Symposium on Operating Systems Design and Implementation
PDF

Exploiting Nil-Externality for Fast Replicated Storage
Aishwarya Ganesan, Ramnatthan Alagappan, Andrea C. Arpaci-Dusseau, Remzi H. Arpaci-Dusseau
28th ACM Symposium on Operating Systems Principles
PDF, Talk Slides, Video - short, Video - long, Code
Invited to Transactions on Storage

The Storage Hierarchy is Not a Hierarchy: Optimizing Caching on Modern Storage Devices with Orthus
Kan Wu, Zhihan Guo, Guanzhou Hu, Kaiwei Tu, Ramnatthan Alagappan, Rathijit Sen, Kwanghyun Park, Andrea C. Arpaci-Dusseau, Remzi H. Arpaci-Dusseau
19th USENIX Conference on File and Storage Technologies
PDF

From Wisckey to Bourbon: A Learned Index for Log-structured Merge Trees
Yifan Dai, Yien Xu, Aishwarya Ganesan, Ramnatthan Alagappan, Brian Kroth, Andrea C. Arpaci-Dusseau, Remzi H. Arpaci-Dusseau
Proceedings of the 14th Symposium on Operating System and Design Implementation
PDF

Can Applications Recover from fsync Failures?
Anthony Rebello, Yuvraj Patel, Ramnatthan Alagappan, Andrea C. Arpaci-Dusseau, Remzi H. Arpaci-Dusseau
The 2020 USENIX Annual Technical Conference
PDF
Invited to Transactions on Storage

Strong and Efficient Consistency with Consistency-aware Durability
Aishwarya Ganesan, Ramnatthan Alagappan, Andrea C. Arpaci-Dusseau, Remzi H. Arpaci-Dusseau
18th USENIX Conference on File and Storage Technologies
PDF, Talk Slides
Best Paper Award
Invited to Transactions on Storage

Fault-Tolerance, Fast and Slow: Exploiting Failure Asynchrony in Distributed Systems
Ramnatthan Alagappan, Aishwarya Ganesan, Jing Liu, Andrea C. Arpaci-Dusseau, Remzi H. Arpaci-Dusseau
Proceedings of the 13th Symposium on Operating System and Design Implementation
PDF, Talk Slides

Protocol-Aware Recovery for Consensus-Based Storage
Ramnatthan Alagappan, Aishwarya Ganesan, Eric Lee, Aws Albarghouthi, Vijay Chidambaram, Andrea C. Arpaci-Dusseau, Remzi H. Arpaci-Dusseau
Proceedings of the 16th USENIX Conference on File and Storage Technologies
PDF, Talk Slides
Best Paper Award
Invited to Transactions on Storage
Invited to ATC 19 Best of the Rest
Coverage: Morning Paper, zdnet

Atomic In-Place Updates for Non-Volatile Main Memories with KaminoTx
Amir Saman Memaripour, Anirudh Badam, Amar Phanishayee, Yanqi Zhou, Ramnatthan Alagappan, Karin Strauss, Steven Swanson
Proceedings of the Twelfth European Conference on Computer Systems
PDF

Redundancy Does Not Imply Fault Tolerance: Analysis of Distributed Storage Reactions to Single Errors and Corruptions
Aishwarya Ganesan, Ramnatthan Alagappan, Andrea C. Arpaci-Dusseau, Remzi H. Arpaci-Dusseau
Proceedings of the 15th USENIX Conference on File and Storage Technologies
PDF, Talk Slides, Code
Best Paper Award Nominee
Invited to Transactions on Storage
Invited to Usenix ;login:
Coverage: StorageMojo, Morning Paper, DHSR's blog

Application Crash Consistency and Performance with C2FS
Thanumalayan Sankaranarayana Pillai, Ramnatthan Alagappan, Lanyue Lu, Vijay Chidambaram, Andrea C. Arpaci-Dusseau, Remzi H. Arpaci-Dusseau
Proceedings of the 15th USENIX Conference on File and Storage Technologies
PDF, Talk Slides
Best Paper Award
Invited to Transactions on Storage
Invited to ATC 17 Best of the Rest
Coverage: Morning Paper

Correlated Crash Vulnerabilities
Ramnatthan Alagappan, Aishwarya Ganesan, Yuvraj Patel, Thanumalayan Sankaranarayana Pillai, Andrea C. Arpaci-Dusseau, Remzi H. Arpaci-Dusseau
Proceedings of the 12th Symposium on Operating System and Design Implementation
PDF, Talk Slides, Code

All File Systems Are Not Created Equal: On the Complexity of Crafting Crash-Consistent Applications
Thanumalayan Sankaranarayana Pillai, Vijay Chidambaram, Ramnatthan Alagappan, Samer Al Kiswany, Andrea C. Arpaci-Dusseau, Remzi H. Arpaci-Dusseau
Proceedings of the 11th Symposium on Operating System and Design Implementation
PDF, Code
Invited to Communications of the ACM
Invited to ACM Queue
Coverage: Morning Paper

Fall 2022: CS 598 Storage Systems: Theory and Practice
Fall 2022: CS 591 SN Systems Seminar



Teaching at Wisconsin
Instructor for CS 739 - Spring 2020 (co-taught by Aishwarya Ganesan).
Evaluation (as an intructor): 6.42/7.00 (ranked 2nd among graduate courses)
Nominated for the SACM CoW award (yearly teaching award given to UW CS professors)
Evaluation (course as a whole): 6.50/7.00 (ranked 1st among all courses)
I designed a graduate-level distributed systems course. This course was heavily research oriented: every class, students read 1-2 foundational papers in distributed systems on topics including fault tolerance, consensus (e.g., Paxos), distributed transactions, BFT, and distributed storage. Students also did a considerably large research project. Lecture notes, assignments, and exams are available on the course web page.

Teaching Assistant for CS 537 Introduction to Operating Systems
Responsibilities: Guest lectures, exam review lectures, designing and evaluating assignments on the xv6 research operating system.

Guest Lectures
Shivaram Venkatramans’s CS 537 (concurrency, RAID)
Mike Swift’s CS 736 (AFS)
Remzi Arpaci-Dusseau’s CS 739 - (Paxos, storage faults)

Teaching Assistant for CS 302 Introduction to Programming
Responsibilities: Designing and evaluating programming assignments in Java.

We are currently looking for students to join our group DASSL at Illinois.

In the past, I have had the great pleasure of working with the following students.
VMware Research
Yi Xu, graduate student at UC San Diego

Undergraduate Students at UW Madison
Neil Perry, now a graduate student at Stanford University

Graduate Students at UW Madison
Yifan Dai, Yien Xu
Dax Chen, Yi-Shiun Chang, Chia-Wei Chen, Pei-Hsuan Wu
Sreya Dutta Roy, Nikita Kad, Venkat Allam, Shreeshrita Patnaik
Akshat Jain, Grishma Gupta, Venkata Malireddy
Ruohui Wang, Kaiwei Tu, Max (Mengxiao) Zhang, Emma (Yi) He
Aashish Richhariya, Akanksha, Sanchit Jain
Muthunagappan Muthuraman, Srivatsan Ramesh, Suryadev Sahadevan Rajesh, Vinith Venkatesan
Deepak Srinath, Lokit Kumar Paras, Nithin Venkatesh, Phanindra Moganti
Kumar Biplav, Aditya Rungta, Nisarg Shah, Shaurya Shekhar

Service

Program Committee OSDI '23
Poster Co-chair FAST '23
Program Committee SOCC '22
Program Committee HotStorage '22
Ask-Me-Anything Co-chair SOSP '21
OSDI Mentoring OSDI '21
EuroDW Mentoring EuroDW '21
Journal of Systems SEB Co-cair '21
EuroDW Program Committee EuroDW '21
Program Committee HotStorage '21 (Distinguished Reviewer)
Program Committee Systor '21
Reviewer ACM Transactions on Computer Systems '20
Program Committee HotStorage '20
Artifact Evaluation Committee Reviewer SOSP '19
Shadow Program Committee Reviewer Eurosys '19 (Best Reviewer Award)
Reviewer ACM Transactions on Storage '18
External Reviewer FAST '18
Contributor to PC reviews Eurosys '17
External Reviewer OSDI '16
External Reviewer FAST '16

Presentations and Invited Talks

Co-designing Distributed Systems and Storage Stacks for Improved Reliability

• University of Waterloo Jan '22
• Virginia Tech Jan '22
• Pennsylvania State University Feb '22
• University of Virginia Feb '22
• Purdue University Feb '22
• University of Utah Feb '22
• University of Toronto Mar '22
• University of Illinois at Urbana-Champaign Mar '22
• University of Washington Mar '22
• University of Michigan Mar '22
• Massachusetts Institute of Technology Mar '22
• University of North Carolina at Chapel Hill Mar '22
• University of Southern California Mar '22
• University of California, Santa Cruz Mar '22
• University of California, Irvine Apr '22

Co-designing Distributed Systems and Storage Stacks @ Waterloo Oct 21 (invited)
Reliable Distributed Storage: A Local Storage Perspective @ Rutgers Aug 20 (invited)
Reliable Distributed Storage: A Local Storage Perspective @ VRG Jun 20 (postdoc interview talk)
Protocol-Aware Recovery for Consensus-Based Storage @ ATC '19 (invited conference talk)
Storage Systems at the Edge @ NSF-VMWare ECDI Summit (invited)
Fault-Tolerance, Fast and Slow: Exploiting Failure Asynchrony in Distributed Systems @ OSDI '18 (slides)
Protocol-Aware Recovery for Consensus-based Storage @ SNIA SDC '18 (invited, slides, video)
Resiliency to Storage Faults in Distributed Systems @ Google Madison May '18 (invited)
Protocol-Aware Recovery for Consensus-Based Storage @ FAST '18 (slides)
Rethinking Consensus with Local Storage in Mind @ SCI-labs 2017
Correlated Crash Vulnerabilities @ OSDI '16 (slides)
Correlated Crash Vulnerabilities @ Microsoft Gray Systems Lab

PACE: To check for correlated crash vulnerabilities in distributed systems
Code on GitHub
CORDS: To test corruption tolerance in distributed systems
Code on GitHub
ALICE: To check for crash vulnerabilities in local storage systems
Code on GitHub