This guide walks you through every line of the Linux top command output, explaining system summaries, CPU and memory metrics, process details, and advanced shortcuts, so you can quickly diagnose performance bottlenecks and become proficient at real‑time system troubleshooting.
After upgrading a PXA166‑based Chumby 8 from Linux 2.6.28 to 6.x, the top command constantly reported 100% CPU usage, leading the author through profiling, kernel source analysis, procfs inspection, and a timer‑register sequencing bug that was finally fixed by adjusting the delay in the timer_read function.
This guide explains how to use Java's java.lang.management APIs to retrieve real-time JVM CPU usage, system load averages, garbage collection details, and heap/non‑heap memory statistics, providing code snippets and practical usage scenarios for performance testing and resource allocation.
This article explains key system performance testing metrics such as response time, concurrency, click‑through rate, throughput, TPS/QPS, PV/UV, and details essential Linux server indicators like CPU usage, memory utilization, load average, and disk I/O, providing formulas, interpretation guidelines, and useful command‑line tools.
A low‑load performance test compares three ways of selecting an array index—using Math.random(), a sequential int counter, and AtomicInteger—revealing that the random‑number approach consumes significantly more CPU while AtomicInteger spikes memory usage under higher loads.
This tutorial walks you through creating a Bash script that periodically captures and displays memory, disk, and CPU utilization on a Linux server, explains the underlying commands, shows how to run the script in a timed loop, and demonstrates adding a stress test for load generation.
This report analyzes how popular Chrome extensions affect browser performance by increasing CPU usage, slowing page rendering, and consuming additional memory, presenting data from tests on various websites and highlighting the cumulative impact of multiple extensions on user experience.
This article explains what Linux load average actually measures, distinguishes it from CPU utilization, describes runnable and uninterruptible states, and demonstrates its behavior through CPU‑intensive, I/O‑intensive, and high‑process‑count scenarios using common monitoring tools.
The article walks through a real‑world Java production incident where CPU spiked to 100%, detailing systematic troubleshooting steps, heap analysis with MAT, and the discovery that repeatedly creating BouncyCastleProvider objects caused a memory leak that was fixed by refactoring the code.
This guide shows Linux administrators how to use the ps command with sorting and head to list the top ten processes by CPU usage, memory consumption, and virtual memory, explains the meaning of key ps output fields, and provides alternative sorting options.
This guide shows Linux commands for quickly identifying the ten processes that consume the most CPU, memory, or virtual memory, explains the key ps fields, and provides alternative sorting options for system monitoring.
This article introduces the powerful cross‑platform psutil module, explains how to install it, demonstrates basic commands to list processes, retrieve CPU usage, and explore various useful methods, all illustrated with clear code snippets and screenshots.
A Linux laptop with a 4K display suffered extreme CPU usage and fan noise during video playback, which vanished after disabling 200% UI scaling and using a lower resolution with 100% scaling, revealing a scaling‑related bug in the graphics stack.
This article explains the meaning of the Linux uptime/top output, defines system load average as the average number of runnable and uninterruptible processes, distinguishes it from CPU utilization, and provides guidance on interpreting load values for single‑core and multi‑core systems.
This article details the design and implementation of an iOS performance‑monitoring SDK that captures fundamental metrics such as CPU usage, memory consumption, frame rate, cold and hot startup times, and power draw, explains the underlying Mach APIs, provides sample Objective‑C code, and discusses practical considerations for accurate measurement and troubleshooting.
This guide explains how to use the Linux pidstat command to monitor process-level CPU, memory, and I/O statistics, covering column meanings, various command options, and examples for specific processes and child processes.
Optimizing queries should focus on those that, when improved, deliver the greatest overall system benefit—typically high‑concurrency, low‑cost queries—because small savings on frequently run statements can vastly reduce I/O, CPU usage, and risk of catastrophic performance failures.
This article explains how to use the sar (System Activity Reporter) tool on Linux to collect and analyze performance data, covering past and real‑time statistics, CPU, memory, I/O and swap metrics, installation steps, and a full list of command‑line options.
