Github messages for voidlinux
 help / color / mirror / Atom feed
* [ISSUE] Raspberry Pi images use powersave governor by default
@ 2021-11-13  0:35 beadleha
  2021-11-15  6:43 ` mikoxyz
                   ` (4 more replies)
  0 siblings, 5 replies; 6+ messages in thread
From: beadleha @ 2021-11-13  0:35 UTC (permalink / raw)
  To: ml

[-- Attachment #1: Type: text/plain, Size: 2023 bytes --]

New issue by beadleha on void-packages repository

https://github.com/void-linux/void-packages/issues/34049

Description:
The mainline Linux kernel uses `schedutil` as the default cpu frequency governor for both arm and arm64 since version 5.9, and now uses it by default on most other platforms as well. Void for x86/x86_64 currently use `schedutil` by default because of this. However, the Raspberry Pi kernel fork uses `powersave` instead, and then overrides it using the cpufreq package in Raspberry Pi OS. The developers do not seem inclined to change it since the default setting is overridden by Raspberry Pi OS anyway.

Void Linux does not initially override the default setting, so the default governor that the kernel is compiled with is the one that is used. This makes the system extremely slow until the user overrides the kernel's default setting.

My proposal is to add a sed command to the build templates make the kernel follow the default used in mainline kernels. This seems simpler than adding the cpufreq package to the base images. I believe the change would only affect the templates for `rpi-kernel`, `rpi3-kernel`, and `rpi4-kernel`.

And the change could look like this:
    # Set default frequency governor to match mainline kernel
    sed -i 's/CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE=y/CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL=y/g' "$defconfig"

Let me know what you think.

### System

* xuname:  
Void 5.10.52_1 aarch64 Unknown notuptodate rFF
* package:  
rpi4-kernel-5.10.52_1

### Expected behavior
Linux mainline kernel uses `schedutil` by default, including on arm and arm64.
Void generally follows this default from upstream.
I would expect the default governor for Void to also be `schedutil` on my Raspberry Pi.

### Actual behavior
Void for Raspberry Pi uses `powersave` and the system is sluggish until the default is overridden.

### Steps to reproduce the behavior
Check default cpu governor on Void for Raspberry Pi. Compare to default for x86 and x86_64.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: Raspberry Pi images use powersave governor by default
  2021-11-13  0:35 [ISSUE] Raspberry Pi images use powersave governor by default beadleha
@ 2021-11-15  6:43 ` mikoxyz
  2021-11-16  1:13 ` beadleha
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: mikoxyz @ 2021-11-15  6:43 UTC (permalink / raw)
  To: ml

[-- Attachment #1: Type: text/plain, Size: 315 bytes --]

New comment by mikoxyz on void-packages repository

https://github.com/void-linux/void-packages/issues/34049#issuecomment-968583764

Comment:
An alternative would be to stop directly using upstream's defconfig, and instead use a defconfig based on upstream's defconfig that's more similar to our arm(64) defconfig.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: Raspberry Pi images use powersave governor by default
  2021-11-13  0:35 [ISSUE] Raspberry Pi images use powersave governor by default beadleha
  2021-11-15  6:43 ` mikoxyz
@ 2021-11-16  1:13 ` beadleha
  2021-11-16  6:30 ` mikoxyz
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: beadleha @ 2021-11-16  1:13 UTC (permalink / raw)
  To: ml

[-- Attachment #1: Type: text/plain, Size: 632 bytes --]

New comment by beadleha on void-packages repository

https://github.com/void-linux/void-packages/issues/34049#issuecomment-969587371

Comment:
> An alternative would be to stop directly using upstream's defconfig, and instead use a defconfig based on upstream's defconfig that's more similar to our arm(64) defconfig.

That's true, but it would need to be done carefully since there may really be some config settings that are important on some Pi hardware. I don't know for certain whether that is the case. Probably worth doing a diff to see what would actually change and whether it's worth maintaining a separate config over.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: Raspberry Pi images use powersave governor by default
  2021-11-13  0:35 [ISSUE] Raspberry Pi images use powersave governor by default beadleha
  2021-11-15  6:43 ` mikoxyz
  2021-11-16  1:13 ` beadleha
@ 2021-11-16  6:30 ` mikoxyz
  2021-11-24 18:24 ` ahesford
  2021-11-24 18:36 ` beadleha
  4 siblings, 0 replies; 6+ messages in thread
From: mikoxyz @ 2021-11-16  6:30 UTC (permalink / raw)
  To: ml

[-- Attachment #1: Type: text/plain, Size: 725 bytes --]

New comment by mikoxyz on void-packages repository

https://github.com/void-linux/void-packages/issues/34049#issuecomment-969912161

Comment:
> That's true, but it would need to be done carefully since there may really be some config settings that are important on some Pi hardware. I don't know for certain whether that is the case. Probably worth doing a diff to see what would actually change and whether it's worth maintaining a separate config over.

True, though there doesn't seem to be too many Pi-specific options in upstream's defconfig (at least in the bcm2711 defconfig.) I've [attached](https://github.com/void-linux/void-packages/files/7543864/arm64-dotconfig-bcm2711_defconfig.diff.gz) a diff for reference.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: Raspberry Pi images use powersave governor by default
  2021-11-13  0:35 [ISSUE] Raspberry Pi images use powersave governor by default beadleha
                   ` (2 preceding siblings ...)
  2021-11-16  6:30 ` mikoxyz
@ 2021-11-24 18:24 ` ahesford
  2021-11-24 18:36 ` beadleha
  4 siblings, 0 replies; 6+ messages in thread
From: ahesford @ 2021-11-24 18:24 UTC (permalink / raw)
  To: ml

[-- Attachment #1: Type: text/plain, Size: 411 bytes --]

New comment by ahesford on void-packages repository

https://github.com/void-linux/void-packages/issues/34049#issuecomment-978123286

Comment:
```sh
cat <<EOF >> /etc/rc.local
echo schedutil > /sys/devices/system/cpu/cpufreq/policy0/scaling_governor
EOF
```
Problem solved. The RPi kernels are not mainline, they come from the Raspberry Pi foundation. We don't change the scheduler from the dfeault there.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: Raspberry Pi images use powersave governor by default
  2021-11-13  0:35 [ISSUE] Raspberry Pi images use powersave governor by default beadleha
                   ` (3 preceding siblings ...)
  2021-11-24 18:24 ` ahesford
@ 2021-11-24 18:36 ` beadleha
  4 siblings, 0 replies; 6+ messages in thread
From: beadleha @ 2021-11-24 18:36 UTC (permalink / raw)
  To: ml

[-- Attachment #1: Type: text/plain, Size: 542 bytes --]

New comment by beadleha on void-packages repository

https://github.com/void-linux/void-packages/issues/34049#issuecomment-978130508

Comment:
> Problem solved.

The fact is that defaults matter, and we have the ability change what the default is in Void. If the current default is less desirable than some other default, why wouldn't we change it? Void's mainline kernel overrides some config, and this one can too, if we decide it's worth it. I think it is, but am looking to see if there is a constructive discussion to be had about it.

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2021-11-24 18:36 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-11-13  0:35 [ISSUE] Raspberry Pi images use powersave governor by default beadleha
2021-11-15  6:43 ` mikoxyz
2021-11-16  1:13 ` beadleha
2021-11-16  6:30 ` mikoxyz
2021-11-24 18:24 ` ahesford
2021-11-24 18:36 ` beadleha

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).