On Sun, 26 Jan 2020 at 06:14, Matthias Petermann <mp%petermann-it.de@localhost> wrote:
Hello everybody,
on my Lenovo X230 (Intel Core i5-3320M CPU @ 2.60GHz) with NetBSD
9.0_RC1 (amd64) I have made a strange observation several times.
Especially under high load (the CPU temperature was well over 90 degrees
Celsius), the computer seemed to be very slow, even after the load
decreased.
The reason seems to be as follows. Under normal conditions I get:
x230Mk4$ sysctl machdep.est.frequency.available
machdep.est.frequency.available = 2601 2600 2500 2400 2300 2200
2100 2000 1900 1800 1700 1600 1500 1400 1300 1200
In the situation described above, I get:
x230Mk4$ sysctl machdep.est.frequency.available
machdep.est.frequency.available = 1200
It seems as if the available clock frequencies are dropped during
operation, so that the computer / OS can no longer clock itself to a
higher step. After a reboot, everything has become normal again.
Another note: I have the feeling that the problem occurs frequently when
I use Qemu VMs (with nvmm) - in my case especially Windows 10 32 bit. It
could of course be the nature that Qemu generates a lot of load and that
this is a thermal problem. In the meantime, I have set estd so that
frequencies above 2200 MHz are avoided, hoping to get overheating under
control and not get the problem. So far, that hasn't really helped.
Has anyone ever observed something like this and knows advice?
I saw something similar on a T430 under NetBSD-8, I *think* most often
after suspect/resume, possibly when the battery was towards the lower
end.
Not more than another data point unfortunately
David