From mboxrd@z Thu Jan 1 00:00:00 1970 From: Riccardo Vestrini Subject: Re: is it really better speedstep-ich vs. p4-clockmod cpufreq driver? Date: Fri, 23 Jul 2004 01:10:07 +0200 Sender: linux-laptop-owner@vger.kernel.org Message-ID: <4100494F.1020803@sssup.it> References: <40FF88BE.2090507@sssup.it> Mime-Version: 1.0 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: List-Id: Content-Type: text/plain; charset="iso-8859-1"; format="flowed" To: linux-laptop@vger.kernel.org Jim Carter wrote: > On Thu, 22 Jul 2004, Riccardo Vestrini wrote: >>it seems that speedstep-ich and acpi cpufreq driver have only two=20 usable clock >>frequencies, while p4-clockmod has eight >>my cpu is: Intel Mobile Intel(R) Pentium(R) 4 CPU 3.06GHz stepping = 09 >=20 >=20 > Definitely the voltage modulation is important to have. you right, but I do not know if it is better to have a 0.3 GHz clock=20 most of the time, or a 1.5 GHz with half voltage >=20 > Also as for strategies, if you have dynamic speed modulation, general= ly if > the CPU is busy less than 73% of the time, then my machine should be = run at > the lowest speed, whereas if tasks are waiting to run then it should = be put > in the highest speed. In a typical workload it's very rare for the n= eeded > throughput to be steadily between 73% and 100% so the intermediate sp= eeds > could be useful; this is true even if the available speed range is gr= eater. =20 > Actually, hardly anyone uses the full capacity of their CPU, and I do= n't > even bother to run the dynamic modulation daemon, just leaving it at = low > speed all the time. I switch manually if I have a big simulation to = do. >=20 it is the same for me, cpu is almost always set to the lowest frequency= ,=20 but I often compile programs, so I need the full power I consider strange the fact that a more specific driver=20 (speedstep-ich) is not able to put my laptop to half voltage + mininum=20 clock (which is 0.3 GHz) while p4-clockmod is only able to adjust clock= =20 and not voltage; probably these capabilities can be merged some way ... I will try to write the authors thank you --=20 Riccardo Vestrini "Io ho una deformazione professionale, sono Ingegnere, e il problema in quello che lei dice =E8 l'essere umano, perch=E9 una macchina pu=F2 sba= gliare ma l'essere umano ha sicuramente molti pi=F9 difetti" -- sconosciuto ad un congresso, mentre un manager parlava di risorse umane - To unsubscribe from this list: send the line "unsubscribe linux-laptop"= in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html