tuned-ppd.service fails to start with KeyError and TunedException

[0x70369]

Hello. I'm on Arch Linux with tuned version 2.27.0 and some custom profiles. They can be viewed in my repository.

With the configuration stored there, tuned-ppd fails to start every time:

$ systemctl status tuned-ppd.service
× tuned-ppd.service - PPD-to-TuneD API Translation Daemon
     Loaded: loaded (/usr/lib/systemd/system/tuned-ppd.service; enabled; preset: disabled)
     Active: failed (Result: exit-code) since Wed 2026-04-15 19:57:51 -03; 4min 39s ago
 Invocation: bad41ee0b1664ed0a9998c0e184eeedb
    Process: 568680 ExecStart=/usr/bin/tuned-ppd -l (code=exited, status=1/FAILURE)
   Main PID: 568680 (code=exited, status=1/FAILURE)
   Mem peak: 18.5M
        CPU: 108ms

abr 15 19:57:51 Alienware tuned-ppd[568680]:   File "/usr/lib/python3.14/site-packages/tuned/ppd/controller.py", line 436, in switch_profile
abr 15 19:57:51 Alienware tuned-ppd[568680]:     if not self._set_tuned_profile(self._config.ppd_to_tuned.get(profile, self._on_battery)):
abr 15 19:57:51 Alienware tuned-ppd[568680]:                                    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^
abr 15 19:57:51 Alienware tuned-ppd[568680]:   File "/usr/lib/python3.14/site-packages/tuned/ppd/config.py", line 31, in get
abr 15 19:57:51 Alienware tuned-ppd[568680]:     return profile_map[profile]
abr 15 19:57:51 Alienware tuned-ppd[568680]:            ~~~~~~~~~~~^^^^^^^^^
abr 15 19:57:51 Alienware tuned-ppd[568680]: KeyError: 'alienware-balanced'
abr 15 19:57:51 Alienware systemd[1]: tuned-ppd.service: Main process exited, code=exited, status=1/FAILURE
abr 15 19:57:51 Alienware systemd[1]: tuned-ppd.service: Failed with result 'exit-code'.
abr 15 19:57:51 Alienware systemd[1]: Failed to start PPD-to-TuneD API Translation Daemon.

If inside the ppd.conf file I change default=balanced to, say, default=alienware-balanced, this other error shows up instead:

$ systemctl status tuned-ppd.service
× tuned-ppd.service - PPD-to-TuneD API Translation Daemon
     Loaded: loaded (/usr/lib/systemd/system/tuned-ppd.service; enabled; preset: disabled)
     Active: failed (Result: exit-code) since Wed 2026-04-15 20:04:58 -03; 1s ago
 Invocation: 86a007319b124847a21f8d387d42350b
    Process: 621244 ExecStart=/usr/bin/tuned-ppd -l (code=exited, status=1/FAILURE)
   Main PID: 621244 (code=exited, status=1/FAILURE)
   Mem peak: 18.5M
        CPU: 124ms

abr 15 20:04:58 Alienware tuned-ppd[621244]:                    ~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
abr 15 20:04:58 Alienware tuned-ppd[621244]:   File "/usr/lib/python3.14/site-packages/tuned/ppd/config.py", line 47, in __init__
abr 15 20:04:58 Alienware tuned-ppd[621244]:     self.load_from_file(config_file)
abr 15 20:04:58 Alienware tuned-ppd[621244]:     ~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^
abr 15 20:04:58 Alienware tuned-ppd[621244]:   File "/usr/lib/python3.14/site-packages/tuned/ppd/config.py", line 118, in load_from_file
abr 15 20:04:58 Alienware tuned-ppd[621244]:     raise TunedException("Default profile '%s' missing in the profile mapping" % self._default_profile)
abr 15 20:04:58 Alienware tuned-ppd[621244]: tuned.exceptions.TunedException: Default profile 'alienware-balanced' missing in the profile mapping
abr 15 20:04:58 Alienware systemd[1]: tuned-ppd.service: Main process exited, code=exited, status=1/FAILURE
abr 15 20:04:58 Alienware systemd[1]: tuned-ppd.service: Failed with result 'exit-code'.
abr 15 20:04:58 Alienware systemd[1]: Failed to start PPD-to-TuneD API Translation Daemon.

How can I fix this?

[yarda]

IMHO you should change it the following way:

[main]
# The default PPD profile
default=balanced
battery_detection=true
sysfs_acpi_monitor=true

[profiles]
# PPD = TuneD
power-saver=powersave
balanced=alienware-balanced
performance=throughput-performance

[battery]
# PPD = TuneD
balanced=alienware-balanced

Because the PPD API balanced is something different than the TuneD balanced. I.e. in the [main] section it's config for the PPD default profile, which knows only power-saver, balanced, and performance and in the [profiles] and [battery] sections there are mappings of the PPD profiles to TuneD profiles. But the PPD code should be fixed not to traceback in such case.

[0x70369]

I see, thanks for clarifying this part. However, setting the ppd.conf file according to your suggestion didn't fix the problem, unfortunately:

$ systemctl status tuned-ppd.service
× tuned-ppd.service - PPD-to-TuneD API Translation Daemon
     Loaded: loaded (/usr/lib/systemd/system/tuned-ppd.service; enabled; preset: disabled)
     Active: failed (Result: exit-code) since Wed 2026-04-15 20:22:28 -03; 6s ago
 Invocation: 86a03196b63740df924d05ec70f55fe3
    Process: 694706 ExecStart=/usr/bin/tuned-ppd -l (code=exited, status=1/FAILURE)
   Main PID: 694706 (code=exited, status=1/FAILURE)
   Mem peak: 18.3M
        CPU: 89ms

abr 15 20:22:28 Alienware tuned-ppd[694706]:   File "/usr/lib/python3.14/site-packages/tuned/ppd/controller.py", line 436, in switch_profile
abr 15 20:22:28 Alienware tuned-ppd[694706]:     if not self._set_tuned_profile(self._config.ppd_to_tuned.get(profile, self._on_battery)):
abr 15 20:22:28 Alienware tuned-ppd[694706]:                                    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^
abr 15 20:22:28 Alienware tuned-ppd[694706]:   File "/usr/lib/python3.14/site-packages/tuned/ppd/config.py", line 31, in get
abr 15 20:22:28 Alienware tuned-ppd[694706]:     return profile_map[profile]
abr 15 20:22:28 Alienware tuned-ppd[694706]:            ~~~~~~~~~~~^^^^^^^^^
abr 15 20:22:28 Alienware tuned-ppd[694706]: KeyError: 'alienware-balanced'
abr 15 20:22:28 Alienware systemd[1]: tuned-ppd.service: Main process exited, code=exited, status=1/FAILURE
abr 15 20:22:28 Alienware systemd[1]: tuned-ppd.service: Failed with result 'exit-code'.
abr 15 20:22:28 Alienware systemd[1]: Failed to start PPD-to-TuneD API Translation Daemon.

[yarda]

Interesting, I cannot reproduce. With the config provided:

# systemctl status tuned-ppd
● tuned-ppd.service - PPD-to-TuneD API Translation Daemon
     Loaded: loaded (/usr/lib/systemd/system/tuned-ppd.service; enabled; preset: enabled)
    Drop-In: /usr/lib/systemd/system/service.d
             └─10-timeout-abort.conf
     Active: active (running) since Thu 2026-04-16 01:40:52 CEST; 15s ago
 Invocation: 256b33681bd84fea80a4ee628baddd5a
   Main PID: 92941 (tuned-ppd)
      Tasks: 4 (limit: 9289)
     Memory: 18.9M (peak: 19.5M)
        CPU: 325ms
     CGroup: /system.slice/tuned-ppd.service
             └─92941 /usr/bin/python3 -Es /usr/sbin/tuned-ppd -l

# tuned-adm active
Current active profile: alienware-balanced

The same when running on battery, tuned-2.27.0. It's on Fedora, I may try later on Arch.

[0x70369]

Well, that's odd... I'll see if I can spin up a Fedora installation tomorrow to test if this will work.

[yarda]

Well, try changing the content of the: /etc/tuned/ppd_base_profile to balanced, there maybe leftover config (the alienware-balanced profile) from the previous crash.

[yarda]

Well, try changing the content of the: /etc/tuned/ppd_base_profile to balanced, there maybe leftover config (the alienware-balanced profile) from the previous crash.

But it's definitely bug, that should be fixed.

[0x70369]

I changed ppd_base_profile to balanced and now the service is running fine... which is weird because it hasn't worked since I first changed ppd.conf, i.e. the only changes I've done the first time were in the [profiles] section.

Moreover, why would setting ppd_base_profile cause the service to crash? Is it the same reason you explained earlier?

EDIT: after a full system upgrade and a reboot, the service started again, without issues. I guess that's a W?

[yarda]

TuneD PPD stores the last profile used there to know what to restore on next boot. It shouldn't write invalid data there and if it's using this file, it should validate the content. We will address it.

[0x70369]

Alright, thanks for the help. I confirmed that manually writing alienware-balanced to /etc/tuned/ppd_base_profile will raise the KeyError I initially reported.

If you eventually need it, I'll gladly help with further testing. Should I keep this issue open?