Transactional Memory Research Receives OOPSLA Distinguished Paper Award

Writer(s): Kristyn Childres

Doctoral student Keith Chapman and co-authors Antony Hosking of Purdue and Eliot Moss of the University of Massachusetts – Amherst received a Distinguished Paper Award at this year’s 2016 OOPSLA conference for their paper “Hybrid STM/HTM for Nested Transactions on OpenJDK.”

Transactional memory (TM) has long been advocated as a promising pathway to more automated concurrency control for scaling concurrent programs running on parallel hardware. Software TM (STM) has the benefit of being able to run general transactional programs, but with significant overhead cost.

Recently, hardware manufacturers have begun to offer commodity hardware TM (HTM) support in their processors wherein the transaction metadata is maintained “for free” in hardware. However, HTM approaches cannot successfully run all transactional programs, whether because of hardware capacity issues or compatibility restrictions. In such cases, programs must include failure-handling code to attempt the computation by some other software means, since retrying the transaction would be futile.

Chapman, Hosking and Eliot’s paper describes how software and hardware schemes can combine seamlessly into a hybrid system in support of transactional programs, allowing use of low-cost HTM when it works, but reverting to STM when it doesn’t. Learn more.