boot.kernel.sysfs ‐ NixOS ‐ Searchix

boot.kernel.sysfs

sysfs attributes to be set as soon as they become available.

Attribute names represent path components in the sysfs filesystem and cannot be . or .. nor contain any slash character (/).

Names may contain shell‐style glob patterns (*, ? and […]) matching a single path component, these should however be used with caution, as they may produce unexpected results if attribute paths overlap.

Values will be converted to strings, with list elements concatenated with commata and booleans converted to numeric values (0 or 1).

null values are ignored, allowing removal of values defined in other modules, as are empty attribute sets.

List values defined in different modules will not be concatenated.

This option may only be used for attributes which can be set idempotently, as the configured values might be written more than once.

Type

open submodule of nested attribute set of null or sysfs attribute values

Default

{ }

Example

{
  # enable transparent hugepages with deferred defragmentaion
  kernel.mm.transparent_hugepage = {
    enabled = "always";
    defrag = "defer";
    shmem_enabled = "within_size";
  };

  devices.system.cpu = {
    # configure powesave frequency governor for all CPUs
    # the [0-9]* glob pattern ensures that other paths
    # like cpufreq or cpuidle are not matched
    "cpu[0-9]*" = {
      scaling_governor = "powersave";
      energy_performance_preference = 8;
    };

    # disable frequency boost
    intel_pstate.no_turbo = true;
  };
}

Declared