#context switch

[abhisheykgaur]

Context Switching in Operating Systems: Internals, Costs, and Optimization

Every time you open a new tab in your browser, run a terminal command, or use a text editor alongside Spotify, your operating system is managing multiple tasks seemingly at once. This multitasking magic hinges on a low-level OS mechanism called context switching.

In this article, we’ll explore how context switching works in detail, what data is saved and restored, how much it costs in performance, and how modern OS kernels optimize it. If you’ve ever wondered how CPUs handle multiple processes efficiently, this one’s for you. Read More: https://abhisheykgaur.wordpress.com/2025/06/20/context-switching-in-operating-systems-internals-costs-and-optimization/

[amigoccs]

每日一文：切換降低整體效率

董明珠称空调一晚一度电都是骗人的：企业不敢再打这样的广告

“而實際情況是環境溫度是不斷變化的，空調需要根據溫度變化來進行調節。並且往往關機再啟動是最費電的，這個過程可能就需要一兩度電。”

如果在撰寫軟體與文件的過程中，還需要切換支援不同的專案與參與會議中，也同樣會消磨開發人員的專注力，每一次的切換都需要時間成本，整體進度反而被拖慢。

降低多工作業下對開發過程產生負面衝擊的方法有兩種：

1. 減少心神 (mind) 切換 - David Stiernholm 建議每人每天不超過兩個會議；尊重勿擾狀態，避免用即時通訊、電話、談天打斷；用 Daily Scrum Meeting 安排當天工作項目，讓開發者可以自行規劃

2. 減少需要長期高專注力的時間 - 改用 No-Code / Code-less Platform，安排系統管理者用設定 (Configuration) 滿足部分功能需求，分攤開發人員的工作量，降低撰寫程式、測試、與撰寫文件的時間。

在我的 Salesforce 導入經驗中，第二種方法對於現有的開發人員是最困難的。因爲他們習慣從程式設計的角度思考，熟悉平臺可程式化物件 (programmable Objects) 勝於系統設定。建議直接找一個能與使用者溝通能夠的系統管理員，最省事也最快看到效果。

[airbornemihir]

Linger over your context switches.

Make them unhurried and reflective.

Think about why you’re starting something different.

You’re a person, not a microprocessor. People can learn a lot more than machines - if only they would learn to pause and think at the right moment, which is when they start something new or different.

Also, if you find you don’t really have a reason to context switch - go right back to what you were doing before. Microprocessors gotta be fair to everything that asks for their time - you don’t.

[javaonjava]

What is Context Switching in Java?

Swicth

One important concept to be understood before moving forward is Context Switching. 

When multiple processes share a single CPU, they fight for the CPU time. It is via context switching that each of them gets some CPU time slice. 

In very basic terms, one process should be switched out of CPU so that another process can run. 

Similar context switching can be understood at the JVM level for a single process which has many threads.

[evanwilde]

Sometimes it feels like I am living multiple lives. There are three of us renting the basement suite. I'm always around, but it seems that the other two have some sort of mutual exclusion thing going on. When one comes back, the other is gone, when the other is back, the one is gone. It is kind of weird since they are both quite different in their behaviour, one is more of a math-guy, the other is quite emotional. I'm happy that I can handle context switches pretty quickly, but the discussions are quite different. 

I wonder if I should name my threads after my room mates, and call the critical sections of code "home" for my operating system homework. I like that idea.