Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 07 Oct 2015 23:18:38 +0000
From:      bugzilla-noreply@freebsd.org
To:        freebsd-bugs@FreeBSD.org
Subject:   [Bug 202651] cpufreq no longer works in 10.2 on Intel D525MWV
Message-ID:  <bug-202651-8-MdkWCiOwow@https.bugs.freebsd.org/bugzilla/>
In-Reply-To: <bug-202651-8@https.bugs.freebsd.org/bugzilla/>
References:  <bug-202651-8@https.bugs.freebsd.org/bugzilla/>

next in thread | previous in thread | raw e-mail | index | archive | help
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D202651

--- Comment #1 from Viktor =C5=A0tujber <viktor.stujber@gmail.com> ---
After failing to find the regression window and discovering that the previo=
us
kernel with the new userland also exhibits the problem, I again tried searc=
hing
for existing discussions about the subject.

I found
https://lists.freebsd.org/pipermail/freebsd-stable/2015-March/082034.html f=
rom
march 2015 which points to a 1 year old change in HEAD,
https://svnweb.freebsd.org/base?view=3Drevision&revision=3D265329 . Here the
committer references some other mailing list discussion, which concluded th=
at
P-state power management is not effective and can interfere with C-state po=
wer
management.

That is nice and all, but this Intel Atom CPU does not have any C-state pow=
er
management. Using P-states has a measurable impact (a few watts). Undoing t=
he
changes to /boot/device.hints is what I did for now.

--=20
You are receiving this mail because:
You are the assignee for the bug.=



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?bug-202651-8-MdkWCiOwow>