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Title: Efficient and Safe I/O Operations for Intermittent Systems
Task-based intermittent software systems always re-execute peripheral input/output (I/O) operations upon power failures since tasks have all-or-nothing semantics. Re-executed I/O wastes significant time and energy and risks memory inconsistency. This paper presents EaseIO, a new task-based intermittent system that remedies these problems. EaseIO programming interface introduces re-execution semantics for I/O operations to facilitate safe and efficient I/O management for intermittent applications. EaseIO compiler front-end considers the programmer-annotated I/O re-execution semantics to preserve the task's energy efficiency and idem-potency. EaseIO runtime introduces regional privatization to eliminate memory inconsistency caused by idempotence bugs. Our evaluation shows that EaseIO reduces the wasted useful I/O work by up to 3× and total execution time by up to 44% by avoiding 76% of the redundant I/O operations, as compared to the state-of-the-art approaches for intermittent computing. Moreover, for the first time, EaseIO ensures memory consistency during DMA-based I/O operations.  more » « less
Award ID(s):
2107400 2145584
PAR ID:
10418308
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Proceedings of the Eighteenth European Conference on Computer Systems (EuroSys ’23)
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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