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Title: Transactional Causal Consistency for Serverless Computing
We consider the setting of serverless Function-as-a-Service (FaaS) platforms, where storage services are disaggregated from the machines that support function execution. FaaS applications consist of compositions of functions, each of which may run on a separate machine and access remote storage. The challenge we address is improving I/O latency in this setting while also providing application-wide consistency. Previous work has explored providing causal consistency for individual I/Os by carefully managing the versions stored in a client-side data cache. In our setting, a single application may execute multiple functions across different nodes, and therefore issue interrelated I/Os to multiple distinct caches. This raises the challenge of Multisite Transactional Causal Consistency (MTCC): the ability to provide causal consistency for all I/Os within a given transaction even if it runs across multiple physical sites. We present protocols for MTCC implemented in a system called HYDROCACHE. Our evaluation demonstrates orders-of-magnitude performance improvements due to caching, while also protecting against consistency anomalies that otherwise arise frequently.  more » « less
Award ID(s):
1730628
PAR ID:
10221241
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
SIGMOD '20: Proceedings of the 2020 ACM SIGMOD International Conference on Management of Data
Page Range / eLocation ID:
83 to 97
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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