HAWEN: Hardware Accelerator for Thread Wake-Ups in Linux Event Notification

Lars Nolte, Tim Twardzik, Camille Jalier, Zhigang Huang, Jiyuan Shi, Clara Kowalsky, Thomas Wild, Andreas Herkersdorf

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

1 Scopus citations


The performance of multi-threaded applications relies on efficient inter-process communication. One common practice is putting a thread asleep while waiting for a certain condition. Exemplary Linux kernel mechanisms that use this practice include futex, sockets, epoll, eventfd and pipe. Once the condition is met, i.e., the associated event has occurred, the waiting thread is notified. Optimizations for event notification mechanisms in Linux mostly target the thread which receives events. Contrarily, we identified high potential in relieving the event-generating thread and propose HAWEN, a hardware accelerator for thread wake-up support. HAWEN has been integrated into Linux event notification in a minimally intrusive manner. Gem5-based multi-core architecture simulations revealed up to 80% faster thread wake-up times and a 53% shorter event-generating syscall.

Original languageEnglish
Title of host publication2023 60th ACM/IEEE Design Automation Conference, DAC 2023
PublisherInstitute of Electrical and Electronics Engineers Inc.
ISBN (Electronic)9798350323481
StatePublished - 2023
Event60th ACM/IEEE Design Automation Conference, DAC 2023 - San Francisco, United States
Duration: 9 Jul 202313 Jul 2023

Publication series

NameProceedings - Design Automation Conference
ISSN (Print)0738-100X


Conference60th ACM/IEEE Design Automation Conference, DAC 2023
Country/TerritoryUnited States
CitySan Francisco


  • Event notification
  • Gem5
  • Linux kernel
  • Thread wake-up


Dive into the research topics of 'HAWEN: Hardware Accelerator for Thread Wake-Ups in Linux Event Notification'. Together they form a unique fingerprint.

Cite this