After I had installed Arch Linux and the X system on my ThinkPad X200 notebook, I noticed bad performance. The mouse always stopped moving. The system was quite busy with itself and had a high cpu load – too high in my opinion. I already had this issue on my Ubuntu 11.04 system.
According to other blog posts, this issue has something to do with intel graphics adapters. Unfortunately, I don’t have the time to investigate this issue in detail here.
The solution there was to disable the DRM_KMS_HELPER polling feature of the kernel. There is a good tutorial here which describes, how to do that.
But now, I own an Arch Linux box, so how are things done here? Well, quite easy. To disable polling temporarily, enter the following command on the shell (you need root privileges to do that):
echo N> /sys/module/drm_kms_helper/parameters/poll
If you would like your changes to survice a reboot, just add the following line to your /etc/modprobe.d/modprobe.conf file:
options drm_kms_helper poll=N
After having put this option in place, system response time was much better.