Tune system performance with tuned profiles

tuned is a service that applies a consistent set of system settings, a profile, suited to the use of the machine. Rather than adjusting dozens of kernel, CPU and disk parameters by hand, you choose a profile (throughput-performance for a server, powersave to save energy, virtual-guest for a VM) and tuned takes care of the rest. This guide shows how to list the profiles, see the active one, let tuned recommend the right one, change it and verify it is applied. For intermediate administrators, mainly on RHEL and derivatives. The RHCSA objectives (EX200, RHEL 10) name it explicitly: "Manage tuning profiles", under Operate running systems. Outputs come from an AlmaLinux 10 test (tuned 2.27), packages and paths also checked on Debian 13 (2.25.1) and Ubuntu 24.04 (2.21.0).

What you will learn

• What a tuned profile is and where the profiles live.
• Install and enable the tuned service.
• List the profiles and identify the active profile.
• Let tuned recommend a profile according to the role of the machine.
• Change the profile and verify it is applied.

What is a tuned profile

A profile groups settings aimed at one goal: maximise throughput, minimise latency, save energy. Each profile adjusts parameters such as the CPU frequency governor, disk caching or sysctl values, without you having to know them.

The profiles shipped by the distribution live under /usr/lib/tuned/profiles/; your own profiles, under /etc/tuned/profiles/. This layout comes with recent versions of tuned: on Ubuntu 24.04 (tuned 2.21.0), each profile still sits directly under /usr/lib/tuned/<name>/, and a custom profile under /etc/tuned/<name>/. A custom profile with the same name as a system profile replaces it, which lets you start from an existing profile and adjust it.

Each profile is a readable tuned.conf file. The one of throughput-performance, for example, sets vm.swappiness=10, and virtual-guest, which includes it, raises the value to 30 (read in the files): an active profile therefore often explains a sysctl value that does not match the kernel default.

Install and enable tuned

On RHEL and derivatives, tuned is often already present. Elsewhere, install it, then enable the service.

RHEL/AlmaLinux

sudo dnf install tuned

Debian/Ubuntu

sudo apt update
sudo apt install tuned

sudo systemctl enable --now tuned
systemctl is-active tuned

The output must show active. All the administration then goes through a single command, tuned-adm, which talks to the daemon.

List the profiles and see the active one

tuned-adm list shows the available profiles with a description, and flags the active profile at the bottom. The list depends on the distribution: RHEL 10 ships about fifteen profiles in the tuned package and puts the others (mssql, oracle, postgresql, cpu-partitioning...) in tuned-profiles-* packages, whereas Debian and Ubuntu ship more than thirty at once:

tuned-adm list

Available profiles:
- balanced                 - General non-specialized tuned profile
- powersave                - Optimize for low power consumption
- throughput-performance   - Broadly applicable tuning ... common server workloads
- latency-performance      - Optimize for deterministic performance ...
- virtual-guest            - Optimize for running inside a virtual guest
- virtual-host             - Optimize for running KVM guests
...
Current active profile: virtual-guest

To get only the current profile, use tuned-adm active, which prints a single line.

Which profile for which use

The profile names are explicit, but here are the common choices in production. They all appear in tuned-adm list on AlmaLinux 10 and Ubuntu 24.04; the Debian 13 package (tuned 2.25.1) does not ship virtual-host (measured):

Use of the machine	Suitable profile
Application server, database, general server use	throughput-performance
Latency-sensitive load (real time, VoIP, trading)	latency-performance or network-latency
Virtual guest machine	virtual-guest
KVM virtualisation host	virtual-host
Workstation, laptop	balanced, or powersave on battery
Intensive computing (HPC)	hpc-compute

Swipe to see more

When in doubt, balanced is the all-purpose default profile. A wrong choice breaks nothing: the worst risk is a suboptimal machine, never unstable, and a simple tuned-adm profile puts it right.

Let tuned recommend a profile

If you hesitate, tuned-adm recommend suggests the profile suited to the detected role of the machine. On a VM, it logically advises virtual-guest:

tuned-adm recommend

virtual-guest

It is also what tuned applies by default at the first start, through the auto_profile mode.

Change the profile

To apply a profile, pass its name to tuned-adm profile. The change is immediate and persists after reboot:

sudo tuned-adm profile throughput-performance
tuned-adm active

Current active profile: throughput-performance

To disable every tuned setting and go back to the default values of the system, use tuned-adm off.

`tuned-adm off` is persistent, and it takes a command to get out of it

It is not a deactivation "for the time of a test". The command changes two state files, and the machine stays without a profile at the next reboot:

File	Before off	After off
/etc/tuned/active_profile	virtual-guest	empty
/etc/tuned/profile_mode	auto	manual

Swipe to see more

The switch to manual is what makes the effect lasting: tuned will no longer ask tuned-adm recommend which profile to apply. So the way back is not reapplying a profile, but:

sudo tuned-adm auto_profile

The rollback of the settings, for its part, is real and logged (terminating TuneD, rolling back all changes): vm.dirty_ratio goes back for example from 30 to 20.

A corollary to know: setting a profile by hand with tuned-adm profile <name> also switches profile_mode to manual, silently. These two files carry the real state of the machine, read them when in doubt.

Verify that a profile is applied

tuned-adm verify compares the settings in force with those expected by the active profile, and says whether they match:

sudo tuned-adm verify

verify often fails in a virtual machine

In a VM, tuned-adm verify frequently returns Verification failed, current system settings differ from the preset profile. It is normal: part of the settings of a profile targets real hardware (CPU governor, physical disk parameters) that the hypervisor does not let the guest drive.

Do not count on a systemctl restart tuned to make these failures go away: they cannot be removed in a virtual machine. Measured on AlmaLinux 10 with tuned 2.27, after a service restart, /var/log/tuned/tuned.log keeps the same lines:

WARNING  tuned.plugins.plugin_cpu: Unable to set boost on cpu 'cpu0'.
         Neither per-policy boost nor intel_pstate no_turbo is available.
ERROR    tuned.plugins.base: verify: failed: device cpu0: 'boost' = 'None', expected '1'

Only the sysctl lines pass. A student who expects a clean verify in a VM will look for a fault that does not exist. On physical hardware, verify must pass; if it fails, that is when the log becomes useful.

Put it into practice

A performance profile is not judged on paper. On a disposable VM, this lab makes you install tuned, compare the suggestion of tuned-adm recommend with the active profile, then apply a new profile and check it with tuned-adm verify.

Guided lab Practice

Learn how to do it

Apply a tuned performance profile

$ dsoxlab run l3-tuned-profile

Environment: VM·Duration: ~20 min

How it is checked: the state of the system is checked after a reboot, not the command you typed.

First time? What DSOXLab is and how to install it

DSOXLab is the command line that prepares a disposable environment (an isolated shell or a VM), runs the lab scenario, then checks the real state of the system and computes a score. Nothing is installed or broken on your workstation.

It needs Python 3.11 or later, uv or pipx, and git. The installation guide details these prerequisites; on Windows, or on a Mac without Python, use the appliance instead.

This lab starts virtual machines: it also needs ansible-playbook, a hypervisor (KVM or Incus), Terraform and hardware virtualization (/dev/kvm), which inside a VirtualBox VM means nested virtualization. The first time, dsoxlab start l3-tuned-profile checks all of it before creating the machines. Prepare your machine for vm labs.

Install the CLI and add the catalogue, once:

uv tool install dsoxlab   # or: pipx install dsoxlab
dsoxlab catalog add https://github.com/stephrobert/linux-dsoxlab-training

Before you run the lab, check:

• DSOXLab installed
• catalogue available
• compatible environment (isolated shell or VM)

To check, nothing is probed from this page: run dsoxlab doctor. Read the diagnosis

Run this lab, then validate your work:

dsoxlab run l3-tuned-profile
dsoxlab check l3-tuned-profile

See every lab: dsoxlab list-labs. Track your progress: dsoxlab progress. The full dsoxlab guide covers scoring and the pitfalls.

Key points

• A tuned profile applies a consistent block of settings for a given use, without setting each parameter by hand.
• All the administration goes through tuned-adm: list, active, recommend, profile <name>, verify, off.
• Choose according to use: throughput-performance (server), latency-performance (real time), powersave (energy), virtual-guest (VM).
• tuned-adm recommend suggests the profile suited to the role of the machine.
• A profile change persists after reboot; verify can fail legitimately in a VM.

Knowledge check

Check that the essentials of this guide stuck. The questions cover only what has just been explained here.

Knowledge check

Check what you have learned with this interactive quiz

6 questions

6 min

70% to pass

How it works

• The timer starts when you click Start
• Multiple choice, true/false and short answer questions
• You can move between questions
• Detailed results are shown at the end

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