Reduced I/O Latency with Futures

Kyle Singer; Kunal Agrawal; I-Ting Angelina Lee

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arXiv · 1906.08239

Reduced I/O Latency with Futures

Kyle Singer·Kunal Agrawal·I-Ting Angelina Lee

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Abstract

Task parallelism research has traditionally focused on optimizing computation-intensive applications. Due to the proliferation of commodity parallel processors, there has been recent interest in supporting interactive applications. Such interactive applications frequently rely on I/O operations that may incur significant latency. In order to increase performance, when a particular thread of control is blocked on an I/O operation, ideally we would like to hide this latency by using the processing resources to do other ready work instead of blocking or spin waiting on this I/O. There has been limited prior work on hiding this latency and only one result that provides a theoretical bound for interactive applications that use I/Os. In this work, we propose a method for hiding the latency of I/O operations by using the futures abstraction. We provide a theoretical analysis of our algorithm that shows our algorithm provides better execution time guarantees than prior work. We also implemented the algorithm in a practically efficient prototype library that runs on top of the Cilk-F runtime, a runtime system that supports futures within the context of the Cilk Plus language, and performed experiments that demonstrate the efficiency of our implementation.

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BibTeX RIS

Kyle Singer, Kunal Agrawal, I-Ting Angelina Lee. 2019-06-19. Reduced I/O Latency with Futures. https://arxiv.org/abs/1906.08239

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