Inside the ComputerOperating Systems

The Spinning Beach Ball

One busy task can freeze an entire app

You tap a button and the whole app stops answering, even the button to close it. What is it stuck on?

You'll find out

  • Why one slow job freezes everything
  • How long each frame has to get ready
  • How smooth apps hide their slow work

Why it matters

Every app you use juggles slow work. Where it runs explains why some apps freeze and others never do.

About 3 min6 interactive slides · 5 questionsLesson 220 · Zone 25

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