[CentOS] browsers slowing Centos 7 installation to a crawl

Sun Aug 4 17:38:29 UTC 2019
Michael Hennebry <hennebry at web.cs.ndsu.nodak.edu>

My video problems mentioned in a previous thread are gone,
though I do not know why.

Now my problem is that whenever I have a
browser open and an internet connection,
my Centos 7 slows to a crawl.
Chromium seems to be the least bad.
Sometimes it slows to the point that I cannot even move the mouse.
Even switching between virtual terminals takes a while sometimes.
When I get there, top generally shows me between two and five D states.
I've changed service providers lately.
The problem survived the change.
Some sites seem to aggravate the problem.
Most recently, a site tried to connect to c.amazon.adsystem.com .
I got the message waiting for c.amazon.adsystem.com .
I have that address in my hosts file as .
ping finds it and pings.
nslookup does not:
> [hennebry at localhost ~]$ nslookup c.amazon.adsystem.com
> Server:
> Address:
> ** server can't find c.amazon.adsystem.com: NXDOMAIN

Whether the slow-to-crawl problem is related to the failure to redirect,
I do not know.
The former is clearly more important.
Any suggestions on how to diagnose it?
Any ideas on why chromium is waiting for c.amazon.adsystem.com
and how I can fix it?

Michael   hennebry at web.cs.ndsu.NoDak.edu
"Sorry but your password must contain an uppercase letter, a number,
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