Re: Improving KDE Plasma Performance on Low-Resource Systems

On Sat, 2026-08-22 at 18:59 +0300, Konstantin Kharlamov wrote:
> On Mon, 2026-08-17 at 10:13 +0300, Lost Nebula wrote:
> > 
> > 
> > Dear KDE developers,
> > 
> > I know that GNOME and KDE Plasma are modern and feature-rich
> > desktop
> > environments. However, I believe that performance and resource
> > efficiency should receive much more attention in the future,
> > especially for low-end computers and tablets.
> > 
> > My system is a good example of this problem: **an Intel Atom Z3735
> > processor, 1 GB of physical RAM, 1 GB of ZRAM, and 1 GB of disk
> > swap**. Even with 1 GB of ZRAM and an additional 1 GB of disk swap,
> > running GNOME or KDE Plasma puts an extremely heavy load on the
> > system.
> 
> I don't think your description fits an average lower-performance
> system. I see two problems in your configuration, both heavily
> influencing your poor experience, and I kind of hope other users of
> similarly old/low-end hardware have no these.
> 
> 1. 1G of disk SWAP. Like, why? Allocate at least 8G, what are you
> afraid of? Swap storms? Well, fear not: modern Linux kernel for
> multiple years has MLRU that was contributed by Google with focus on
> SWAP performance on Android devices, and that's enabled by default in
> pretty much every popular distro. MLRU allows kernel to choose "cold
> memory" much better, so you have much less probability that
> application
> would try to use memory that's residing on disk/in swap.
> 2. You're using ZRAM with SWAP, that's just wrong. You want either
> "just ZRAM" or "ZSWAP + SWAP". Your combination of "ZRAM + SWAP"
> isn't
> going to give you the experience you expect. I can refer you to this
> article that goes deeper into this topic:
> https://chrisdown.name/2026/03/24/zswap-vs-zram-when-to-use-what.html
> 
> -------
> 
> If you have specific points to improve when these configuration
> problems are fixed, I think it could be interesting to discuss. But
> as
> you currently represent the situation, there's just nothing specific
> to
> KDE (or to any DE for that matter).

Oh, and…

3. …make sure you have "swappiness" set to 100. Idk what you have it
set to, but you want MGLRU to work hard for you, which ain't happening
if you set swappiness to like 10 forcing the kernel to drop FS caches
instead of swapping out cold anon pages.

P.S.: also, sorry I misspelled "MGLRU" as "MLRU", hopefully it didn't
confuse anyone though, I don't think there's any distinct "MLRU" term.