Re: [DistroKit] [PATCH v3 1/4] x86_64: kernel: update config

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

Hi,

On 5/5/26 1:17 PM, Lucas Stach wrote:
>  CONFIG_UTS_NS=y
> -CONFIG_TIME_NS=y
> +# CONFIG_TIME_NS is not set

Just spitballing here: With an eye towards Y2038, do we maybe want to
keep this enabled?

- Positive Offset: Enable isolated testing of components with y2038 time
- Negative Offset: Run proprietary components that were't fixed in the past?

> +CONFIG_INITRAMFS_PRESERVE_MTIME=y

FWIW, I normally disable this as this is just extra work that I don't
see the need for in my BSPs.

Quoting 1274aea127b2 ("initramfs: add INITRAMFS_PRESERVE_MTIME Kconfig
option"):

"""
This change adds a new INITRAMFS_PRESERVE_MTIME Kconfig option, which
can be used to disable on-by-default mtime retention and in turn speed
up initramfs extraction, particularly for cpio archives with large
directory counts.

Benchmarks with a one million directory cpio archive extracted 20 times
demonstrated:
                                mean extraction time (s)        std dev
INITRAMFS_PRESERVE_MTIME=y              3.808                    0.006
INITRAMFS_PRESERVE_MTIME unset          3.056                    0.004
"""

Granted my initramfs are probably not big enough to matter, but still
why do the extra work?



> -CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE=y
> +# CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE is not set
>  # CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE is not set
>  # CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE is not set
> -# CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL is not set
> +CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL=y

The thinking so far was that performance gives us the best boot time and
then we would switch to a more suitable default from userspace.

Is this outdated practice?

Thanks,
Ahmad

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