nixos-generate-config: detect CPU governor

* cpu-freq: Try powersave if ondemand is not available

* Revert "cpu-freq: Try powersave if ondemand is not available"

This reverts commit 4dc56db37e.
Consult available scaling governors; for freshly generated configs, this provides a better experience than relying on a default that might not work everywhere.
This commit is contained in:
gnidorah 2017-01-02 19:20:28 +03:00 committed by Joachim F
parent 3c1ade7d15
commit 90deca3a0c
2 changed files with 16 additions and 1 deletions

View File

@ -69,7 +69,7 @@ in
config = mkIf cfg.enable {
# FIXME: Implement powersave governor for sandy bridge or later Intel CPUs
# Leftover for old setups, should be set by nixos-generate-config now
powerManagement.cpuFreqGovernor = mkDefault "ondemand";
systemd.targets.post-resume = {

View File

@ -94,6 +94,21 @@ sub hasCPUFeature {
my $cpus = scalar (grep {/^processor\s*:/} (split '\n', $cpuinfo));
# Determine CPU governor to use
if (-e "/sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors") {
my $governors = read_file("/sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors");
# ondemand governor is not available on sandy bridge or later Intel CPUs
my @desired_governors = ("ondemand", "powersave");
my $e;
foreach $e (@desired_governors) {
if (index($governors, $e) != -1) {
last if (push @attrs, "powerManagement.cpuFreqGovernor = \"$e\";");
}
}
}
# Virtualization support?
push @kernelModules, "kvm-intel" if hasCPUFeature "vmx";
push @kernelModules, "kvm-amd" if hasCPUFeature "svm";