Bio
I’m a researcher at the Microsoft Research, Silicon Valley. My research interests span the broad area of Operating Systems, specifically focusing on file and storage systems. In my past life, I was a graduate student at the Computer Sciences Department of the University of Wisconsin, Madison where I did my doctorate under the guidance of Prof. Andrea C. Arpaci-Dusseau and Prof. Remzi H. Arpaci-Dusseau.
Research
My recent research interests revolve around solid state devices (SSDs). We evaluated the design tradeoffs in building an SSD to understand how they affect the application performance and device lifetime [usenix'08]. We have built an SSD simulator by extending the DiskSim simulator (from CMU) with an SSD module. The simulator has options to evaluate different SSD designs and cleaning/wear-leveling algorithms. We evaluated various designs using traces from both real-world workloads and file system benchmarks. In summary, we find that the performance and lifetime of an SSD depends on a variety of factors: complexity of firmware (i.e., the specific algorithm that runs on the firmware), types of flash packages, interconnection, and workloads. The simulator is available for download.
I lead the "Transactional Flash" project, where we propose a richer, transactional interface for an SSD. Certain characteristics of an SSD such as fast random access and copy-on-write semantics make it a suitable medium to support the transactional features. An important contribution of this work is a novel cyclic commit protocol, which ensures atomicity of transactions without using additional commit block writes. More details about this work is available our recent paper [osdi'08].
In the summer of 2008, we wanted to understand if traditional assumptions made at the higher level software stack (e.g., file systems) still hold under SSDs. The results of our study will appear as a short paper [usenix'09].
I'm interested in the reliability aspects of file and storage systems as well. We are currently examining techniques for automatic recovery from data structure corruptions, specifically from file system's perspective. Current file system checkers often do a poor job of recovering from corruptions; they are often heuristics-based, ad-hoc, and local. In Crystal, we are casting the problem of recovery as a global optimization problem that searches across various repairs to find a set of least-cost repairs that satisfy all the data structure invariants. You can read about this methodology in our upcoming paper [hotdep'09]. In the past, I have worked on understanding how file systems handle I/O failures and what can one do to improve their reliability in the context of IRON File Systems and IO Shepherd [sosp'05, sosp'07] .
I'm a member of the Flashlight project.
- Gokul Soundararajan, Vijayan Prabhakaran, Mahesh Balakrishnan, and Ted Wobber, Griffin: Extending SSD Lifetimes with Disk-Based Write Caches, in FAST 2010: 8th USENIX Conference on File and Storage Technologies (To Appear), USENIX, February 2010
- Michael Isard, Vijayan Prabhakaran, Jon Currey, Udi Wieder, Kunal Talwar, and Andrew Goldberg, Quincy: Fair Scheduling for Distributed Computing Clusters, in Proceedings of 22nd ACM Symposium on Operating Systems Principles, Association for Computing Machinery, Inc., 11 October 2009
- Asim Kadav, Mahesh Balakrishnan, Vijayan Prabhakaran, and Dahlia Malkhi, Differential RAID: Rethinking RAID for SSD Reliability, in HotStorage 2009: 1st Workshop on Hot Topics in Storage and File Systems, Association for Computing Machinery, Inc., October 2009
- Hongyi Wang, Bingsheng He, Vijayan Prabhakaran, and Lidong Zhou, Crystal: The Power of Structure Against Corruptions, in Proceedings of the Fifth Workshop on Hot Topics in System Dependability (HotDep'09), 29 June 2009
- Abhishek Rajimwale, Vijayan Prabhakaran, and John D. Davis, Block Management in Solid-State Devices, in Proceedings of the USENIX Annual Technical Conference (USENIX'09), USENIX, June 2009
- Vijayan Prabhakaran, Thomas L. Rodeheffer, and Lidong Zhou, Transactional Flash, in Proceedings of the 8th USENIX Symposium on Operating Systems Design and Implementation (OSDI ’08), USENIX, December 2008
- Nitin Agrawal, Vijayan Prabhakaran, Ted Wobber, John D. Davis, Mark Manasse, and Rina Panigrahy, Design Tradeoffs for SSD Performance, in Proceedings of the 2008 USENIX Technical Conference (USENIX'08), USENIX, June 2008
- Lidong Zhou, Vijayan Prabhakaran, Venugopalan Ramasubramanian, Roy Levin, and Chandramohan A. Thekkath, Graceful degradation via versions: specifications and implementations, in Symposium on Principles of Distributed Computing (PODC 2007), Portland, OR, August 2007
- Haryadi S. Gunawi, Vijayan Prabhakaran, Swetha Krishnan, Andrea C. Arpaci-Dusseau, and Remzi H. Arpaci-Dusseau, Improving file system reliability with I/O shepherding, in Proceedings of Twenty-First ACM SIGOPS Symposium on Operating Systems Principles (SOSP'07), Association for Computing Machinery, Inc., 2007
- Andrea C. Arpaci-Dusseau, Remzi H. Arpaci-Dusseau, Lakshmi N. Bairavasundaram, Timothy E. Denehy, Florentina I. Popovici, Vijayan Prabhakaran, and Muthian Sivathanu, Semantically-Smart Disk Systems: Past, Present, and Future, in Sigmetrics Performance Evaluation Review (PER), Association for Computing Machinery, Inc., 2006
- Vijayan Prabhakaran, Lakshmi N. Bairavasundaram, Nitin Agrawal, Haryadi S. Gunawi, Andrea C. Arpaci-Dusseau, and Remzi H. Arpaci-Dusseau, IRON file systems, in Proceedings of the twentieth ACM symposium on Operating Systems Principles (SOSP'05), Association for Computing Machinery, Inc., 2005
- Vijayan Prabhakaran, Andrea C. Arpaci-Dusseau, and Remzi H. Arpaci-Dusseau, Model-Based Failure Analysis of Journaling File Systems, in Proceedings of the International Conference on Dependable Systems and Networks (DSN-2005), IEEE Computer Society, 2005
- Vijayan Prabhakaran, Andrea C. Arpaci-Dusseau, and Remzi H. Arpaci-Dusseau, Analysis and Evolution of Journaling File Systems, in Proceedings of the USENIX Annual Technical Conference (USENIX'05), USENIX, 2005
- Muthian Sivathanu, Vijayan Prabhakaran, Andrea C. Arpaci-Dusseau, and Remzi H. Arpaci-Dusseau, Improving Storage System Availability with D-GRAID, in ACM Transactions on Storage (TOS), Association for Computing Machinery, Inc., 2005
- Vijayan Prabhakaran, Andrea C. Arpaci-Dusseau, and Remzi H. Arpaci-Dusseau, Analysis and Evolution of a Journaling File System, June 2004
- Muthian Sivathanu, Vijayan Prabhakaran, Andrea C. Arpaci-Dusseau, and Remzi H. Arpaci-Dusseau, Improving Storage System Availability with D-GRAID, in Proceedings of the Third USENIX Symposium on File and Storage Technologies (FAST'04), USENIX, 2004
- Muthian Sivathanu, Vijayan Prabhakaran, Florentina Popovici, Timothy E. Denehy, Andrea C. Arpaci-Dusseau, and Remzi H. Arpaci-Dusseau, Semantically-Smart Disk Systems, in Proceedings of the Second USENIX Symposium on File and Storage Technologies (FAST '03), USENIX, 2003
- Vijayan Prabhakaran, Joseph Stanley, and Paul Barford, High Throughput Data Transfers using the Tornado Transport Protocol, October 2002
