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CPU, Memory, and Disk Pressure Map

Separate CPU, memory, and disk pressure into distinct diagnostic paths instead of calling everything a performance problem.

Matrix

CPU, Memory, and Disk Pressure Map

Performance work gets messy when one symptom leads people to the wrong subsystem. This visual keeps the main pressure signals separate.

Open Processes Open lesson Open lab
Diagram
Layer SignalUsually meansBest next check
High CPU One or more compute-heavy workloads are dominating the scheduler.Identify the top CPU process and confirm whether it should be busy.
High memory pressure Working sets are too large or too many processes are resident.Check the top memory consumers and whether paging or swapping is active.
High disk wait Storage or background I/O is slowing the whole workload.Inspect active reads and writes before blaming the wrong process.
Mixed pressure More than one subsystem is stressed at once.Decide which signal is primary before acting.
What to notice
  • High CPU, low memory, and high disk wait point to different bottlenecks.
  • One overloaded process and broad system pressure are not the same situation.
  • Good diagnosis starts by separating the dominant pressure signal.
Common confusion
  • Calling every slowdown a memory problem.
  • Ignoring disk wait while focusing only on CPU charts.
  • Killing a process before checking whether the issue is wider system pressure.
Related learning
Processes 6 command anchors
Topic hub Commands
Best related lessons
M18 - Process Model: What Processes Are

Understand the difference between a program stored on disk and a process running in memory, and learn the basic ideas of PID, parent process, and thread.

 M20 - Process Management: CLI

List, filter, and stop processes from the command line with a stronger habit of inspecting before terminating.

 M22 - Performance Diagnosis

Check CPU, memory, and disk pressure more systematically so a slow system is diagnosed from evidence instead of guesses.

 M23 - Process Lab: Sluggish System

Use safe practice loads to observe a slow system, identify the cause, and restore normal behavior without guessing or overreacting.
Best related labs
LAB-PROC-03 - Signals and Controlled Stopping

Understand basic process signals and practice stopping harmless processes with a preference for gentler signals first.

 LAB-PROC-05 - Service Persistence: systemd

Understand what systemd is responsible for and practice basic service inspection before attempting custom service creation.

 LAB-MON-01 - Real-time Monitoring (top/htop)

Use top and htop to inspect CPU and memory usage, sort active processes, and stop a disposable practice load.

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