linux-kernel - Re: [patch 2/2] x86: Manage ENERGY_PERF

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20100306064359.GC28759@elf.ucw.cz>
Date:	Sat, 6 Mar 2010 07:43:59 +0100
From:	Pavel Machek <pavel@....cz>
To:	Matthew Garrett <mjg@...hat.com>
Cc:	"Pallipadi, Venkatesh" <venkatesh.pallipadi@...el.com>,
	Randy Dunlap <rdunlap@...otime.net>,
	Ingo Molnar <mingo@...e.hu>, H Peter Anvin <hpa@...or.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Len Brown <lenb@...nel.org>, Dave Jones <davej@...hat.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-acpi@...r.kernel.org" <linux-acpi@...r.kernel.org>
Subject: Re: [patch 2/2] x86: Manage ENERGY_PERF_BIAS based on cpufreq
 governor

On Fri 2010-03-05 22:49:09, Matthew Garrett wrote:
> On Fri, Mar 05, 2010 at 10:13:30PM +0100, Pavel Machek wrote:
> > On Fri 2010-03-05 20:55:22, Matthew Garrett wrote:
> > > On Fri, Mar 05, 2010 at 09:40:29PM +0100, Pavel Machek wrote:
> > > 
> > > > That can be only true if it does not give benefits period... AC and
> > > > battery power are quite different scenarios.
> > > 
> > > No, they're not.
> > 
> > Yes, they are.
> > 
> > Would you care to elaborate? I may very well want top power on AC
> > power, and max powersavings on battery; most people do.
> 
> You may want that. But power constraints aren't limited to battery, and 
> being on battery doesn't inherently mean that you're power constrained. 
> Mixing these concepts results in all kinds of issues.

That's of course true.

But if something gives so limited benefit that it does not make sense
to tweak between power constrained and not-power-constrained
environments (I used AC and battery as an example), it is useless.
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/