Hardening FaaS and improve its performance while preserving genericity

Publié le mer 25/01/2023 - 10:55
Date de début de thèse (si connue)
Des que possible
Unité de recherche
IRISA - UMR 6074
Description du sujet de la thèse


Function as a service (FaaS) is the most recent Cloud model that provides extreme agility to developers. Concretely, with FaaS, users ship their code in a specific format and store it on the Cloud store. Then, they configure events that will trigger the execution of their code e.g., a new tweet on Twitter for an account. At the code termination, the bill considers the total execution time and the memory used by code. FaaS is gaining much traction since it allows users to focus principally on the logic part of their business and leave servers provisioning to the Cloud actors. A recent report shows that the FaaS market will reach 53.08 billion $ by 2028.

A key objective of a FaaS platform is to rapidly trigger the execution of users' code upon the trigger and ensure execution isolation among different users. To achieve that, mainstream FaaS platform use virtualization, concretely: containers, microVMs, or unikernels. Unfortunately, the default boot time of the latter units is not fast enough for FaaS demands. Consequently, several research works propose techniques to improve boot time mainly through snapshotting.



Despite, the existing techniques, there is room for improvement as demonstrated by Cloudflare which proposes an architecture relying on the V8 javascript engine for isolation. With their architecture, they announce boot times of 1ms which outclasses existing designs. However, their architecture comes at the cost of specific constraints for the users' code. Firstly, the size of the code is limited to 1MB. Secondly, their architecture works better for native javascript since for other languages, they use WebAssembly to transform your code to javascript compliant.


In this work, we want to break the limitations of Cloudflare architecture. Concretely, we want to propose a generic design that can be applied per programming language specifications (e.g., Java or Go) so that the benefits are not undermined by WebAssembly.  Additionally, we advocate that current isolation techniques can be improved with hardware instructions provided by vendors. The goal of the work is to assess the Cloudflare architecture, detect the special components related to the V8 to see how to apply them for any existing language, and enhance isolation plus performance through carefully crafted hardware instructions.


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Liste des encadrants et encadrantes de thèse

Nom, Prénom
Yerom-David Bromberg
Type d'encadrement
Directeur.trice de thèse
Unité de recherche

Nom, Prénom
Djob Mvondo
Type d'encadrement
Unité de recherche
Djob Mvondo
FaaS, isolation, performance, Instructions, Hardware