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Title: eZNS: Elastic Zoned Namespace for Enhanced Performance Isolation and Device Utilization
Emerging Zoned Namespace (ZNS) SSDs, providing the coarse-grained zone abstraction, hold the potential to significantly enhance the cost efficiency of future storage infrastructure and mitigate performance unpredictability. However, existing ZNS SSDs have a static zoned interface, making them in-adaptable to workload runtime behavior, unscalable to underlying hardware capabilities, and interfering with co-located zones. Applications either under-provision the zone resources yielding unsatisfied throughput, create over-provisioned zones and incur costs, or experience unexpected I/O latencies. We propose eZNS, an elastic-ZNS interface that exposes an adaptive zone with predictable characteristics. eZNS comprises two major components: a zone arbiter that manages zone allocation and active resources on the control plane, and a hierarchical I/O scheduler with read congestion control and write admission control on the data plane. Together, eZNS enables the transparent use of a ZNS SSD and closes the gap between application requirements and zone interface properties. Our evaluations over RocksDB demonstrate that eZNS outperforms a static zoned interface by 17.7% and 80.3% in throughput and tail latency, respectively, at most.  more » « less
Award ID(s):
2212192
PAR ID:
10525629
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Association for Computing Machinery
Date Published:
Journal Name:
ACM Transactions on Storage
Volume:
20
Issue:
3
ISSN:
1553-3077
Page Range / eLocation ID:
1 to 41
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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