Concurrent Data Structures Linked in Time
Arguments about correctness of a concurrent data structure are typically carried out by using the notion of linearizability and specifying the linearization points of the data structure’s procedures. Such arguments are often cumbersome as the linearization points’ position in time can be dynamic (depend on the interference, run-time values and events from the past, or even future), non-local (appear in procedures other than the one considered), and whose position in the execution trace may only be determined after the considered procedure has already terminated.
In this paper we propose a new method, based on a separation-style logic, for reasoning about concurrent objects with such linearization points. We embrace the dynamic nature of linearization points, and encode it as part of the data structure’s auxiliary state, so that it can be dynamically modified in place by auxiliary code, as needed when some appropriate run-time event occurs. We name the idea linking-in-time, because it reduces temporal reasoning to spatial reasoning. For example, modifying a temporal position of a linearization point can be modeled similarly to a pointer update in separation logic. Furthermore, the auxiliary state provides a convenient way to concisely express the properties essential for reasoning about clients of such concurrent objects. We illustrate the method by verifying (mechanically in Coq) an intricate optimal snapshot algorithm due to Jayanti, as well as some clients.
Thu 22 Jun
|10:30 - 10:55|
Germán Andrés DelbiancoIMDEA Software Institute, Ilya SergeyUniversity College London, Aleksandar NanevskiIMDEA Software Institute, Anindya BanerjeeIMDEA Software InstituteLink to publication Media Attached
|10:55 - 11:20|
Jens DietrichMassey University, David PearceVictoria University of Wellington, Kamil JezekUniversity of West Bohemia, Pilsen, CZ, Premek BradaUniversity of West BohemiaLink to publication Pre-print Media Attached
|11:20 - 11:45|
Jan-Oliver KaiserMPI-SWS, Hoang-Hai DangMPI-SWS, Derek DreyerMPI-SWS, Ori LahavMPI-SWS, Viktor VafeiadisMPI-SWS, GermanyLink to publication Media Attached
|11:45 - 12:10|
Anton PodkopaevSt. Petersburg University, JetBrains, Ori LahavMPI-SWS, Viktor VafeiadisMPI-SWS, GermanyLink to publication Media Attached