KDE Plasma 5.14's Lock Screen Will No Longer Eat Your CPU Resources On Old Hardware

[phoronix]

Phoronix: KDE Plasma 5.14's Lock Screen Will No Longer Eat Your CPU Resources On Old Hardware

With KDE Plasma 5 right now it turns out that if you have relied upon CPU-based software rendering, when hitting Plasma's lock-screen it would actually go CPU-wild -- as far as maxing out the CPU to 100% utilization, thereby consuming a lot of power and generating excess heat. That will be fixed for KDE Plasma 5.14.0...

http://www.phoronix.com/scan.php?page=news_item&px=Plasma-5.14-Fixes-CPU-Lock

[ezst036]

It's great that they fixed this, as some users are on laptops or integrated hardware platforms lacking PCI-E slots.

What I'm really looking forward to is when the support for multiseat within SDDM is completed.

[Adarion]

Why does a simple lock screen (that usually displays nothing but a bland colour and some field to unlock) need all those fancy bells and whistles anyway?

[reavertm]

Why does a simple lock screen (that usually displays nothing but a bland colour and some field to unlock) need all those fancy bells and whistles anyway?

There are lock themes that blur desktop (with all windows open, not just background image), might be one of reasons why.

[DanL]

It's great that they fixed this, as some users are on laptops or integrated hardware platforms lacking PCI-E slots.

Huh? Even if you're using integrated graphics, you should still have hardware-accelerated OpenGL 2.1 except on ancient stuff (Nvidia FX 5000, Intel i8xx, Radeon 9xxx)

[R41N3R]

Sometimes you wonder how these bugs get implemented and why it needs a full Plasma 5.14 to release a fix.

Update: After reading mgaesslin's comment, I think my argument for this specific case doesn't fit, I still am under the impression of all the baloo search engine bugs that consume 100% of a CPU core and have been unfixed way too long.

[Guest]

It's great that they fixed this, as some users are on laptops or integrated hardware platforms lacking PCI-E slots.

What I'm really looking forward to is when the support for multiseat within SDDM is completed.

Integrated graphics cards shipped in the last decade are powerful enough to run Open GL 2.1 and display a lockscreen quite efficiently........this is only a problem for people running without GPU drivers, or with only 2D graphics being hardware accelerated.

[shmerl]

How is the progress of enabling Vulkan in Kwin?

[mgraesslin]

To provide the missing context. The user who reported the bug uses ancient hardware which does not provide OpenGL 2.1. Due to that everything using QtQuick was running on llvmpipe, which is not a good option when running on such old hardware (it seldom has multi-core and SSE4 which makes llvmpipe usable). My reaction to this report was telling the user that I'm sorry, but the hardware does not fulfill the hardware requirements.

David asked the user to try the 2D software renderer option for QtQuick and it turned out that this overall improved the system, but lockscreen was still affected. This was due to the settings not being read in kscreenlocker. David did a change to honor this setting also in kscreenlocker and that's what it's about.

So unless you have hardware which is older than ~10 years you would not hit this bug and even if you would have to run special settings. It's great that it got fixed, but a post here is well, too much attention to nothing.

[Vistaus]

Sometimes you wonder how these bugs get implemented and why it needs a full Plasma 5.14 to release a fix.

Me too. I thought the only DE where parts of it eat your CPU resources was GNOME? Plasma was supposedly much more CPU-friendly, so how did this happen?