Load monitoring widgets get stuck

[solitone]

Hi,

I'm using plasma desktop 5.8.6 on debian stable (stretch). I notice that 
after some time of regular behaviour, load monitoring widgets like CPU 
Load Monitor, Memory Status, and Hard Disk I/O Monitor often get stuck 
and displayed information is not updated any more.

Anyone experiencing the same thing?

Here are the debian packages that I have:

~$ apt-cache policy plasma-desktop
plasma-desktop:
   Installed: 4:5.8.6-1
   Candidate: 4:5.8.6-1
   Version table:
  *** 4:5.8.6-1 500
         500 http://ftp.it.debian.org/debian stretch/main amd64 Packages
         100 /var/lib/dpkg/status

~$ apt-cache policy plasma-widgets-addons
plasma-widgets-addons:
   Installed: 4:5.8.5-2
   Candidate: 4:5.8.5-2
   Version table:
  *** 4:5.8.5-2 500
         500 http://ftp.it.debian.org/debian stretch/main amd64 Packages
         100 /var/lib/dpkg/status