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CompTIA Linux+ XK0-006 · Domain 5: Troubleshooting

Performance: load average, top/htop, vmstat, iostat, sar, free, OOM killer

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Last reviewed September 30, 2026 · Leer en español

When users say a server is slow, you need to find which resource is the bottleneck: CPU, memory, disk I/O (input/output) or something else. The approach is to observe first, identify the constrained resource, then find the process responsible. Each tool below answers part of that question, and exam scenarios usually give you tool output and ask what it means.

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