I defended my PhD thesis, “TTCC: Transactional-Turn Causal Consistency”, in Paris on Friday 21st April 2023 at 14:00 (Paris Time). My PhD research was completed within the LIP6 with the Delys INRIA team and under the supervision of Marc Shapiro.
The official manuscript is available here.
Thesis defense live video
Jury members
- Reviewer: Achour Mostefaoui
Professor, Université de Nantes - Reviewer: Gaël Thomas
Professor, Telecom SudParis - Examiner: Bernd Amann
Professor, Sorbonne Université, LIP6 - Examiner: Annette Bieniusa
Professor, Université Technique de Kaiserslautern - Examiner: Carla Ferreira
Associate Professor, Université NOVA de Lisbon - Examiner: Peter Van Roy
Professor, Université Catholique de Louvain - Supervisor: Marc Shapiro
Distinguished Research Scholar (Emeritus), Sorbonne Université, LIP6, Inria - Advisor: Mesaac Makpangou
Researcher, Sorbonne Université, LIP6, Inria
Abstract
Today, stateful serverless functions are chained together through a message-based infrastructure and store their durable state in a separate database. This separation between storage and compute creates serious challenges that may lead to inconsistency and application crashes.
A unified consistency model for message passing and shared memory is required to avoid such errors. The model should ensure that multiple pieces of data remain mutually consistent, whether data is sent using messages or shared in a distributed memory.
Based on a well-known message-based model (actors) and a state model (transactional shared memory), we propose a unified communication and persistence model called Transactional Turn Causal consistency (TTCC). TTCC is asynchronous, preserves isolation, and ensures that the message and memory view are mutually causally consistent.