On my low RAM/CPU netbook it is a game changer; thanks to ZRAM the netbook is perfect for browsing the internet/light work. When running my backups (creates big tarballs) or Ansible though, my desktop/applications would freeze/stutter noticeably. Enabling MGLRU simply solved the problem of freezes/stuttering, it feels like magic and besides ZRAM, I don’t know of any other lever with this massive impact on desktop performance.
Just wanted to share this, for other users with low RAM/CPU hardware. I would assume the observed difference is less dramatic, once 8GB of RAM are available, but I would love to hear about other experiences.
I would also love to hear/learn about other levers with high impact to tweak for low RAM/CPU desktop devices. Anything else to tweak under /sys /proc which has impact on performance?
I think I did go with LZ4 after looking at benchmarks; I figured on a weak CPU speed would be more valuable than another few percent of compression. I’ll have to look into the RAM page read-ahead.
Just set vm.page-cluster to 0, to disable the page read-ahead (AFAIK the default value was set when swap was still on rotating disks).
Arch wiki has some good options for tuning the VM