How to properly tune zswap with MGLRU?

[Svyatko]

Zswap and MGLRU are usable for Leap 15.6 and 16.0 after manual enabling.
There are some parameters for zswap and for MGLRU. How to properly tune zswap with MGLRU to make them work together properly?

Zswap enlarges available memory (well, not memory, but caches), MGLRU prevents thrashing.

There are 3 technologies for extending RAM: zRam, zswap, zcache.
I’m using zswap because I need swap because examined system has only 2 GiB of RAM.
ILL zcache is the best among these three, but it is abandoned long time ago.

[malcolmlewis]

So just enable it and use zswap-cli (install package) to adjust?

systool -v -m zswap
Module = "zswap"

  Attributes:
    uevent              = <store method only>

  Parameters:
    accept_threshold_percent= "90"
    compressor          = "lzo"
    enabled             = "N"
    max_pool_percent    = "20"
    shrinker_enabled    = "N"

cat /sys/module/zswap/parameters/enabled
N

Oh, and be a real admin, as is su - or use Cockpit, switch to root user and use the terminal session there.

[malcolmlewis]

@Svyatko Since I have a MicroOS/Hyprland setup with only 2GB of system RAM I’ve enabled mglru service and using zram to see if much of a difference. I don’t use this system much, it’s mainly used for terminal use with the likes of minicom connecting to RPi’s and RISCV64 systems, text editing and minimal browsing.

What desktop environment are you running?

 free -h
               total        used        free      shared  buff/cache   available
Mem:           1.8Gi       855Mi       167Mi       112Mi       1.1Gi       972Mi
Swap:          3.6Gi       453Mi       3.1Gi

[malcolmlewis]

Something in action… Using RAM as it should and a bit of zram…

[Svyatko]

@malcolmlewis

What desktop environment are you running?

Optimised KDE 6: baloo is disabled, Akonadi & other KDE PIM are uninstalled.

It turns out Plasma System Monitor consumes 200 MB, but KSysGuard is not available for Leap 16.0: Optimising KDE - alternatives for Plasma System Monitor?

I’m trying htop.

I tried IceWM, but it is not suitable for me using tablet PC.

256 MiB was too much for VRAM, now I use 128 MiB. Lowering to 64 - 96 MiB VRAM - is it suitable?

[malcolmlewis]

@Svyatko You should try hyprland, there is a pattern now in Tumbleweed…

[Svyatko]

Previous discussion:

How to make KDE lighter? Or use another DE?

Using tablet PC with 2 GiB RAM, 1.6 GiB available. Slow 32 GB eMMC, CPU Intel Atom Z3735D, 256 MiB VRAM is dedicated for iGPU. With running Firefox with 3-4 tabs Leap 15.6 uses 1-2 GB of swap. I disabled baloo indexing. I’m going to uninstall Akonadi. What else I can do? Use another DE? Screen rotating works with KDE+Wayland, doesn’t work with KDE+X11. For me CPU is good enough (x86-64-v2, 4 cores), problem is with RAM shortage + slow swap.

@malcolmlewis

hyprland

Available only with Community repo: https://software.opensuse.org/package/hyprland

[malcolmlewis]

Ahh your on Leap 16.0, run MicroOS and use that pattern… It should be in Leap 16.1 which is now underway…

[Svyatko]

Returning to topic: I want to get info from people with experience in using zswap + MGLRU.

[malcolmlewis]

Lets backup some, in another thread your wanting a package built in a ‘Community’ repository, yet because Hyprland for Leap 16.0 is in a ‘Community’ repository you don’t want to try?

I use it, but with zram… it works fine with Hyprland.