---
title: "Space–time tradeoff"
author: "Perrin Yong"
author_profile: https://www.pystone.net/profile/
published_by: "Perrin Yong"
canonical: https://www.pystone.net/notes/space-time-tradeoff/
type: note
content_role: unspecified
visibility: public
id_stability: rename-stable
source_path: "10-计算机、信息技术与工程/01-系统基础与网络安全/计算机与操作系统/Space–time tradeoff.md"
content_hash: 76304878dc3278ab8a4c74a14cd36559b24311e572a36ab3470a6c4de6a80376
knowledge_version: 224c990773de.5fa8af6e39fa
site_commit: 224c990773de166d23a886306577dd90379529ce
notes_commit: 5fa8af6e39fa3891d1b9b4832bfa6c4e0ecaaf0a
---
# Space–time tradeoff

# Space–time tradeoff

> 创建时间：2020/12/28 15:26

A space–time or time–memory trade-off in [computer science](https://en.wikipedia.org/wiki/Computer_science "Computer science") is a case where an [algorithm](https://en.wikipedia.org/wiki/Algorithm "Algorithm") or [program](https://en.wikipedia.org/wiki/Computer_program "Computer program") [trades](https://en.wikipedia.org/wiki/Trade-off "Trade-off") increased space usage with decreased time. Here, space refers to the [data storage](https://en.wikipedia.org/wiki/Computer_storage "Computer storage") consumed in performing a given task ([RAM](https://en.wikipedia.org/wiki/Dynamic_random-access_memory "Dynamic random-access memory"), [HDD](https://en.wikipedia.org/wiki/Hard_disk_drive "Hard disk drive"), etc), and time refers to the time consumed in performing a given task ([computation](https://en.wikipedia.org/wiki/Time_complexity "Time complexity") time or [response time](https://en.wikipedia.org/wiki/Response_time_\(technology\) "Response time \(technology\)")).

The utility of a given space–time tradeoff is affected by related [fixed](https://en.wikipedia.org/wiki/Fixed_cost "Fixed cost") and [variable costs](https://en.wikipedia.org/wiki/Variable_costs "Variable costs") (of, e.g., [CPU](https://en.wikipedia.org/wiki/CPU "CPU") speed, storage space), and is subject to [diminishing returns](https://en.wikipedia.org/wiki/Diminishing_returns "Diminishing returns").

（via. wikipedia: <https://en.wikipedia.org/wiki/Space%E2%80%93time_tradeoff>）