cpupower (from linux-tools / cpupower package) exposes what the kernel cpufreq driver is doing — whether an Intel host is on intel_pstate or legacy ACPI, and whether AMD uses the newer amd-pstate driver with schedutil.
Pair with: nice & ionice,
iostat & vmstat.
See the active driver
cpupower frequency-info shows driver name and available governors.
cpupower frequency-info | grep -E 'driver|governor|limits'

Intel: intel_pstate
Most recent Intel servers use intel_pstate with powersave (hardware-managed boost) or performance for minimum latency — validate thermals and power cap.
cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_driver
# intel_pstate

AMD: amd-pstate / acpi-cpufreq
Newer kernels prefer amd-pstate (ACPI CPPC). Older images may still show acpi-cpufreq. Governor choice affects jitter on low-latency apps.
cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_driver
# amd-pstate_epp or acpi-cpufreq

When to set performance
Batch analytics nodes, small latency-sensitive proxies, or benchmarking baselines — not every 24/7 web tier (power and fan curve). Document before/after with turbostat or cloud metrics.
sudo cpupower frequency-set -g performance
# revert: sudo cpupower frequency-set -g powersave

Quick Reference
- Inspect:
cpupower frequency-info - Driver path:
scaling_driversysfs - Latency lab:
performancegovernor briefly
Related tutorials
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