Title
Concordia: Distributed Shared Memory With In-Network Cache Coherence
Abstract
Distributed shared memory (DSM) is experiencing a resurgence with emerging fast network stacks. Caching, which is still needed for reducing frequent remote access and balancing load, can incur high coherence overhead. In this paper, we propose CONCORDIA, a DSM with fast in-network cache coherence backed by programmable switches. At the core of CONCORDIA is FLOWCC, a hybrid cache coherence protocol, enabled by a collaborative effort from switches and servers. Moreover, to overcome limitations of programmable switches, we also introduce two techniques: (i) an ownership migration mechanism to address the problem of limited memory capacity on switches and (ii) idempotent operations to handle packet loss in the case that switches are stateful. To demonstrate CONCORDIA's practical benefits, we build a distributed key-value store and a distributed graph engine on it, and port a distributed transaction processing system to it. Evaluation shows that CONCORDIA obtains up to 4.2x, 2.3x and 2x speedup over state-of-the-art DSMs on key-value store, graph engine and transaction processing workloads, respectively.
Year
Venue
DocType
2021
PROCEEDINGS OF THE 19TH USENIX CONFERENCE ON FILE AND STORAGE TECHNOLOGIES (FAST '21)
Conference
Citations 
PageRank 
References 
0
0.34
0
Authors
6
Name
Order
Citations
PageRank
Qing Wang155.47
Youyou Lu235630.81
Erci Xu353.97
Junru Li401.35
Youmin Chen5284.24
Jiwu Shu670972.71