Plasmashell polling on zero timeout

Very likely due to plasmashell, the OS hangs/responds very slowly in between while typing or switching tasks or while doing any work. During this hang/slow behaviour, I notice the fan revving in high speed, delay in typing, network disconnection and stuck digital clock seconds counter which restores to normal after the lag subsides but occurs every 10 seconds or so lasting for about 3-4 seconds.

Sysinfo for 'TuxStick': Running inside KDE Plasma 5.7.5 on Ubuntu 16.10 (Yakkety Yak) powered by Linux 4.8.0-26-generic, CPU: Intel(R) Core(TM) i5-5200U CPU @ 2.20GHz at 2099/2700 MHz, RAM: 7443/7902 MB, Storage: 26/57 GB, 283 procs, 65.76h up

health-check output attached