Hello!
We have already discussed this problem in a non-english zone, but I hope that people who can fix this issue will hear us.
In the last few days I noticed that watching videos on YouTube causes the non-paged pool to gradually growing, as well as the memory usage in general. Using Poolmon.exe, I came to the ndis.sys causing the problem. The problem manifests itself in Google Chrome or Opera 55, but not in Microsoft Edge though. I tried to disable NDU, as recommended for this kind of problem, but it did not help. The most interesting part - i noticed that the problem started after updating Avast to 18.6.2349 version, and a person with the same problem said that disabling Avast Web Shield works. And it really does! After disabling Web Shield, the non-paged pool no longer grows. So that's how we found a culprit.
I also talked with one more person with this problem, but he uses the latest version of AVG, and his problem is solved in exactly the same way. Since AVG is a part of Avast, they can share this issue, i guess. So for now i already know 3 people with the same problem.
There is something in Web Shield that causes memory leak.
I do not want to turn off the protection components to make the system stable, so i hope that developers will see this topic and fix the issue as soon as possible.