Twizzler: A Data-centric OS for Non-volatile Memory

Appeared in ACM Transactions on Storage 17(2).


Byte-addressable, non-volatile memory (NVM) presents an opportunity to rethink the entire system stack. We present Twizzler, an operating system redesign for this near-future. Twizzler removes the kernel from the I/O path, provides programs with memory-style access to persistent data using small (64 bit), object-relative cross-object pointers, and enables simple and efficient long-term sharing of data both between applications and between runs of an application. Twizzler provides a clean-slate programming model for persistent data, realizing the vision of Unix in a world of persistent RAM.

We show that Twizzler is simpler, more extensible, and more secure than existing I/O models and implementations by building software for Twizzler and evaluating it on NVM DIMMs. Most persistent pointer operations in Twizzler impose less than 0.5 ns added latency. Twizzler operations are up to 13× faster than Unix, and SQLite queries are up to 4.2× faster than on PMDK. YCSB workloads ran 1.1–2.9× faster on Twizzler than on native and NVM-optimized SQLite backends.

Publication date:
June 2021

Daniel Bittman
Peter Alvaro
Pankaj Mehra
Darrell D. E. Long
Ethan L. Miller

Storage Class Memories
Operating Systems Support for NVM

Available media

Full paper text: PDF

Bibtex entry

  author       = {Daniel Bittman and Peter Alvaro and Pankaj Mehra and Darrell D. E. Long and Ethan L. Miller},
  title        = {Twizzler: A Data-centric {OS} for Non-volatile Memory},
  journal      = {ACM Transactions on Storage},
  volume       = {17},
  number       = {2},
  month        = jun,
  year         = {2021},
Last modified 1 Nov 2021