Basically using plasma 5.3 backport over 15.04, besides the fan working full blown on my laptop the process looks like this:
top - 19:23:40 up 1 day, 8:34, 3 users, load average: 1,98, 2,06, 1,87
Tasks: 242 total, 4 running, 237 sleeping, 0 stopped, 1 zombie
%Cpu(s): 27,2 us, 23,2 sy, 0,1 ni, 49,3 id, 0,2 wa, 0,0 hi, 0,1 si, 0,0 st
KiB Mem: 8083424 total, 3062320 used, 5021104 free, 197264 buffers
KiB Swap: 8294396 total, 0 used, 8294396 free. 1294744 cached Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
17132 th0ma7 20 0 5823844 336280 95268 R 120,2 4,2 103:26.53 plasmashell
897 root 20 0 377664 77544 62892 R 58,8 1,0 51:16.61 Xorg
18826 th0ma7 20 0 1248532 414252 90456 S 19,3 5,1 1:00.49 firefox
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