I haven't verified if this actually fixes the problem but it seems to make a huge difference in 'free' memory as shown by 'free'.
I had already closed my VMs by the time I tried this so haven't verified if it stops the long freezes yet. total used free shared buff/cache available Mem: 31030 5331 2790 5347 22907 19900 Swap: 32767 3130 29637 echo 3 > /proc/sys/vm/drop_caches total used free shared buff/cache available Mem: 31030 5349 17122 5312 8557 19915 Swap: 32767 3130 29637 Notice the 2790 -> 17122 change above in 'free', and 22907 -> 8557 for buff/cache. It appears the kernel doesn't get rid of cache in a reasonable timeframe at the expense of swapping programs out to disk while i/o is happening, which causes gui freezes. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1852001 Title: KDE GUI freeze on high disk IO To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1852001/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs