windows3-5  Exercise 1: Does This Machine Need a Bigger Page File?
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Verification: Level 1 (run on the author's machine, read-only, no administrator rights).

Prediction (work this out before running the script):

  Before running: Microsoft says to consider a bigger page file only if ALL of these are true:
    1. more available physical memory is needed,
    2. the modified page list holds a significant amount,
    3. the page files are fairly full (the usage counter is over 90%).
  Predict, for your machine, whether all three will be true.

Command (pagefile_check.ps1 saved in the current folder):

  .\pagefile_check.ps1

Output (real, from the author's machine on 2026-10-24; your numbers will differ):

  Managed by Windows : True
  Custom size entries: 0
  C:\pagefile.sys: allocated 49,152 MB, in use 138 MB, peak since boot 153 MB (0.3% of allocated)
  Over 20 seconds (averages):
    Page file % usage 0.28   (peak since boot 0.31)
    Pages output/sec  0.0   Pages input/sec 10.3
    Modified list     299 MB   Available 13,735 MB
    Commit charge     26.5 GB of 77.8 GB limit (34%)
    RAM + page file = 31,982,632,960 + 51,539,607,552 = 83,522,240,512 bytes

WHY THIS WORKS AS AN ANSWER
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  Condition 1: Available memory was 13,735 MB (13.4 GB), so no more available memory is needed. Not true.
  Condition 2: the modified list was 299 MB. Microsoft says "several hundred megabytes" normally stays
  resident there and is not written out, so this is not a significant backlog. Not true.
  Condition 3: the page file's usage was 0.28% (peak 0.31%), nowhere near 90%. Not true.
  None of the three holds, so the conclusion is: no change. The 48 GB file is far bigger than this machine uses
  (153 MB peak), but it is also harmless: it is 5% of a disk with 580 GiB free.
  The commit line gives a second, separate check: commit charge 26.5 GB against a limit of 77.8 GB (34%),
  so there is no commit pressure either.
  Common mistakes: judging by the size of the file instead of its usage; reading Pages input/sec as page-file
  reads (Microsoft says hard faults include .dll, .exe and memory-mapped file reads); and treating a single
  20-second reading as the machine's history (the peak figure is since boot, so a heavy day can change it).