PR #256638 inadvertently introduced a bug in `nixos-generate-config` whereby it
would never put `bcache` into the `availableKernelModules` for the initrd.
This is because the `qr` operator in Perl returns a regex object, rather than
matching it; the regex object evaluates to true, making the filter expression
effectively `grep(!true, @bcacheDevices)`, which will always return an empty
list.
This script would always "detect" the "powersave" governor as it is available on
practically all CPUs while the "ondemand" governor is only available on some old
CPUs.
IME the "powersave" governor barely provides any power savings but introduces
massive performance deficits, including noticable stuttering. This is not the
default experience we should offer users, even for those who use laptops.
Use the kernel default (currently "performance", CPU makers may change it in
future) instead.
swraid support will now only be enabled by default if stateVersion is
older than 23.11. nixos-generate-config will now generate explicit
config for enabling support if needed.
The single option tries to do too much work, which just ends up confusing people.
So:
- don't force the console font, the kernel can figure this out as of #210205
- don't force the systemd-boot mode, it's an awkward mode that's not supported
on most things and will break flicker-free boot
- add a separate option for the xorg cursor scaling trick and move it under the xorg namespace
- add a general `fonts.optimizeForVeryHighDPI` option that explicitly says what it does
- alias the old option to that
- don't set any of those automatically in nixos-generate-config
Guest operating systems inside VMs or containers can't update the host CPU's microcode for obvious security reasons, so setting the `hardware.cpu.*.updateMicrocode` options is pointless.
The substr solution assumed a newline to be present.
The new solution will not remove the newline if it goes missing in the future.
Apparently this is idiomatic perl.
Thanks pennae for the suggestion!
Currently we're still using scripted networking by default. A problem
with scripted networking is that having `useDHCP` on potentially
non-existing interfaces (e.g. an ethernet interface for USB tethering)
can cause the boot to hang.
Closes#107908
For imports, it is better to use ‘modulesPath’ than rely on <nixpkgs>
being correctly set. Some users may not have <nixpkgs> set correctly.
In addition, when ‘pure-eval=true’, <nixpkgs> is unset.
Instead of making the configuration less portable by hard coding the number of
jobs equal to the cores we can also let nix set the same number at runtime.
This sets networking.useDHCP to false and for all interfaces found the
per-interface useDHCP to true. This replicates the current default
behaviour and prepares for the switch to networkd.
Up until now, the output has been the same for swap devices and swap
files:
{ device = "/var/swapfile"; }
Whereas for swap *files* it's easier to manage them declaratively in
configuration.nix:
{ device = "/var/swapfile"; size = 8192; }
(NixOS will create the swapfile, and later resize it, if the size
attribute is changed.)
With the assumption that swap files are specified in configuration.nix,
it's silly to output them to hardware-configuration.nix.
Add "bcache" to boot.initrd.availableKernelModules if a bcache device is
detected.
This fixes a problem I've had one too many times: I install NixOS and
forget to add "bcache", resulting in an unbootable machine (until fixed
with Live CD). Now NixOS will do it for me.
This hasn't been needed for a long time, even when `mutableUsers =
false`. Setting a uid manually is potentially risky since it could
collide with non-declarative user accounts. (We do check for
collisions between declarative accounts.)