[arch-general] KDE plasma, baloo and UI/video playback freezes

[Francesco Porro]

So, I finally tried the BFQ scheduler as Carsten suggested.

I tested it eg. using youtube-dl to download a big video from Vimeo (it 
creates/remove quickly a lot of temp files that baloo indexes every time 
causing a lot of IO), while Qbittorrent was downloading several big files... 
So 100% disk activity going on (monitored with iotop).

Overloading the disk queue this way, with BFQ enabled, the result was that the 
video playback of a 1080p movie by VLC was smooth and didn't hang/freeze at 
all. I can assume BFQ was able to handle better all the stuff going on.

So thanks Carsten for the suggestion :) This fixed (or at least worked around) 
the problem.

It remains to understand why on Debian and derivs. this issue doesn't exist. 
Maybe the CONFIG_PREEMPT_VOLUNTARY=y set by default on kernel's config or some 
other block device related configs I don't have the skill (and the time) to 
inspect now.

Cheers

-- 
fp