Comment # 292 on bug 66963 from Weber K.

(In reply to Weber K. from comment #291)
> Hi!
> 
> I have HD 6850 and Kernel 4.4.14.
> 
> This problem appeared for me when I changed rootflags.
> Solved with rootflags=relatime,lazytime,commit=60 in kernel parameters.
> 
> HTH
> 
> Best regards
> Weber Kai

Forgot to mention: And relatime,lazytime,commit=60 in fstab
I believe maybe dpm need some fs information to work well.