Ubuntu 18.04 suddenly has become jumpy and less smooth with fan noise

Question

My system was running fine for a few days after I installed it. But this morning there is the occasional lag of about 0.25- 0.5 seconds as I am scrolling, typing, highlighting, etc. E.g. scrolling works for a moment, then suddenly it stops even though I am rolling the mouse wheel, then starts scrolling again. The effect is very subtle and not serious, but annoying. The same thing happened with Elementary OS every now and again; the problem presented itself then went away, and a few days later it came back again. I don't know if it may be is the system updating itself in the background, but I cannot find anything to show this. If anyone knows what it is I would be interested. I have 16GB RAM and an i7 CPU, NVIDIA graphics card. I have rebooted, and not changed anything. Many thanks

Answer 1

To determine the problem, first go into system settings > details to see if there is anything unusual reported for "graphics."

Also, a good thing to have handy is htop running in the terminal so you can see what process is using system resources.

First, install htop:

sudo apt update
sudo apt install htop 

and then run:

htop 

or optionally, you can run:

sudo htop

with full permissions to allow more control (so you can kill processes).

Additionally, if you want to try using the proprietary nvidia drivers, you can run the following commands to install:

sudo apt update
sudo ubuntu-drivers autoinstall

Save any unsaved work and reboot after the installation to apply the changes.

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Finally, this last step is optional. If you want to use nvidia optimus switching, you can install the bumblebee packages.

First, enable the Universe repository:

sudo add-apt-repository universe

Then, install the packages:

sudo apt update
sudo apt install bumblebee bumblebee-nvidia primus linux-headers-generic mesa-utils

Next, save any unsaved work and then reboot.

Finally, run the following command to monitor your nvidia driver:

nvidia-smi

and run the following command to verify that optimus is running properly:

optirun glxgears

Now, if you get an error running the last command, follow these instructions to properly add your drivers to secureboot.

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UPDATE

It looks like this is a power saving feature. You can monitor CPU performance using the i7z tool to verify throttling.

Run the following to install:

sudo apt update
sudo apt install i7z

and run the tool using the following command:

sudo i7z

You will see the "actual frequency" listed in the output.

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You probably won't need to use the following. However, you can click here for more information about nvidia-smi