Guided path: Memory deep dive
Step 4 of 6
Working set & trimming
Which pages stay resident for a process and how Windows reclaims memory under pressure.
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Why it matters
Working set policy explains why processes get slower under memory pressure even before hard paging dominates.
Mental model
Each process has a working set of resident pages. Under pressure, Windows trims working sets to free frames for others.
How it works
- 1Frequently used pages tend to stay in the process working set.
- 2Memory pressure triggers working set trimming and broader reclaim.
- 3Superfetch and cache manager interact with which file pages stay hot in RAM.
Key terms
- Working set
- Pages currently resident for a process.
- Trim
- Removing pages from a working set to free physical memory.
A game stuttering when many apps are open
Other processes' working sets and the file cache can consume RAM, forcing trims and faults in your foreground app.
Common misconception
Task Manager 'Memory' for a process is not the full story; commit, working set, and private bytes measure different things.
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