I upgraded to Ubuntu 18.04 (from 17.10) yesterday and am currently still running the Unity desktop (same problem in Gnome desktop though).
My problem: I now have a power demand that is about 100% higher than before (around 15W vs. 8W before) without any apparent reason.
As I'm working from my laptop this means that I only get about half the battery life and since the CPU is also heating up quicker my fan is running constantly. I haven't found a quick way to measure the power while plugged in but the CPU heats up just as fast which leads me to believe that the power consumption is high as well.
This is true even when there is no demanding process:
top - 20:45:39 up 13 min, 1 user, load average: 0,15, 0,39, 0,31
Tasks: 249 total, 1 running, 187 sleeping, 0 stopped, 0 zombie
%Cpu(s): 1,3 us, 0,4 sy, 0,0 ni, 98,2 id, 0,0 wa, 0,0 hi, 0,0 si, 0,0 st
KiB Mem : 8041660 total, 4703416 free, 2359324 used, 978920 buff/cache
KiB Swap: 1358960 total, 1358960 free, 0 used. 6148152 avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
2446 patrick 20 0 9349860 735076 154968 S 4,0 9,1 2:13.05 firefox
2519 patrick 20 0 2237800 516520 109456 S 4,0 6,4 1:09.95 Web Content
1106 root 20 0 419312 107380 71488 S 1,7 1,3 0:37.79 Xorg
2004 patrick 20 0 2178352 137972 79436 S 1,3 1,7 0:21.36 compiz
3010 patrick 20 0 803416 38208 28664 S 1,0 0,5 0:00.35 gnome-terminal-
2742 patrick 20 0 1987608 274076 102996 S 0,7 3,4 0:20.37 Web Content
2794 patrick 20 0 1882076 318820 126164 S 0,7 4,0 1:16.83 Web Content
3028 patrick 20 0 44312 4024 3396 R 0,7 0,1 0:00.11 top
1141 root -51 0 0 0 0 S 0,3 0,0 0:03.65 irq/132-nvidia
2063 patrick 20 0 36668 12408 5928 S 0,3 0,2 0:01.14 python3
1 root 20 0 225448 9396 6840 S 0,0 0,1 0:02.16 systemd
Prior to the upgrade I was also running tlp which extended my battery time quite a lot. After the upgrade tlp still seems to be running without any problem (click here for tlp-stat output: http://remmels.org/tlp-stat-output.txt).
Any idea why the power demand went up this much?
It's driving me crazy that I can't figure out where the problem is. At the current state this makes my laptop (1300€, 5 months old) basically useless as I rely on battery power even for work.
Please help me 🙂
Thanks,
Patrick
My machine:
Ideapad 720s-14IKB (https://www3.lenovo.com/us/en/laptops/ideapad/ideapad-700-series/Ideapad-720S-14/p/88IP70S0833)
i7-8550U
8GB DDR4
512GB NVMe SSD
GeForce MX150 (GPU switched to Intel (Power Saving Mode))
Running Ubuntu 18.04 with Unity desktop
Best Answer
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