Re: powerd and increase in energy need
On Thu, Mar 22, 2012 at 7:26 AM, per...@pluto.rain.com wrote: Kevin Oberman kob6...@gmail.com wrote: Throttling ... is intended for thermal control, not power management. The power savings will be negligible ... How can it possibly provide any thermal benefit, if it does not reduce power consumption? Is there some significant heat source, other than power consumed, that throttling reduces? It does not provide reduced power because it was designed to control overheating. If hte CPU does not exceed the PSV temperature, it should not have any effect at all. That is its only purpose. If the system is idle, it makes no difference. If the CPU is loaded, it significantly lowers power consumption, but the operation takes longer to complete, so the total power consumed is often greater than it would have been with no throttling. Again, TCC is for thermal management, not power reduction. As to report I have seen that Cx states make things worse, I simply am baffled. I wonder if the power readings are really accurate. Theoretically the worst possible case is that there is no advantage to enabling Cx states. There should be no possible way to have it use more power. This is a real possibility, too, as it is very possible to have a system that simply would not use deeper sleep states. USB used to do exactly that, but it's been fixed with the new USB stack in 8. Other things like various forms of polling can also have this effect. You can check on whether your system is ever using deeper sleep by looking at dev.cpu.%d.cx_usage. Finally, all studies of power consumption agree that the lowest power usage is when CPU intensive code run as fast as possible when it is computing and then let deeper sleep modes sharply reduce power consumption when CPU is not needed. -- R. Kevin Oberman, Network Engineer E-mail: kob6...@gmail.com ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: powerd and increase in energy need
If you are trying to reduce power consumption, why are you limiting Cx states to C2 (which save little) and not C3 (which will save a LOT of power when the CPU is not heavily loaded). With my hardware, i5-650, using C3 does not result in lower power consumption versus C2. Both states draw exactly the same power. hw.acpi.cpu.cx_lowest: C3 dev.cpu.0.cx_supported: C1/3 C2/205 C3/245 dev.cpu.0.cx_lowest: C3 dev.cpu.1.cx_supported: C1/3 C2/205 C3/245 dev.cpu.1.cx_lowest: C3 dev.cpu.2.cx_supported: C1/3 C2/205 C3/245 dev.cpu.2.cx_lowest: C3 dev.cpu.3.cx_supported: C1/3 C2/205 C3/245 dev.cpu.3.cx_lowest: C3 71w idle power hw.acpi.cpu.cx_lowest: C2 dev.cpu.0.cx_supported: C1/3 C2/205 C3/245 dev.cpu.0.cx_lowest: C2 dev.cpu.1.cx_supported: C1/3 C2/205 C3/245 dev.cpu.1.cx_lowest: C2 dev.cpu.2.cx_supported: C1/3 C2/205 C3/245 dev.cpu.2.cx_lowest: C2 dev.cpu.3.cx_supported: C1/3 C2/205 C3/245 dev.cpu.3.cx_lowest: C2 71w idle power John Theus TheUs Group TheUsGroup.com ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: powerd and increase in energy need
Kevin Oberman kob6...@gmail.com wrote: Throttling ... is intended for thermal control, not power management. The power savings will be negligible ... How can it possibly provide any thermal benefit, if it does not reduce power consumption? Is there some significant heat source, other than power consumed, that throttling reduces? ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: powerd and increase in energy need
If you are trying to reduce power consumption, why are you limiting Cx states to C2 (which save little) and not C3 (which will save a LOT of power when the CPU is not heavily loaded). On my previous post I forgot to set kern.hz=100. This change does lower idle power from 71w to 62w. With my hardware, i5-650, using C3 does not result in lower power consumption versus C2. Both states draw exactly the same power. hw.acpi.cpu.cx_lowest: C3 dev.cpu.0.cx_supported: C1/3 C2/205 C3/245 dev.cpu.0.cx_lowest: C3 dev.cpu.1.cx_supported: C1/3 C2/205 C3/245 dev.cpu.1.cx_lowest: C3 dev.cpu.2.cx_supported: C1/3 C2/205 C3/245 dev.cpu.2.cx_lowest: C3 dev.cpu.3.cx_supported: C1/3 C2/205 C3/245 dev.cpu.3.cx_lowest: C3 62w idle power hw.acpi.cpu.cx_lowest: C2 dev.cpu.0.cx_supported: C1/3 C2/205 C3/245 dev.cpu.0.cx_lowest: C2 dev.cpu.1.cx_supported: C1/3 C2/205 C3/245 dev.cpu.1.cx_lowest: C2 dev.cpu.2.cx_supported: C1/3 C2/205 C3/245 dev.cpu.2.cx_lowest: C2 dev.cpu.3.cx_supported: C1/3 C2/205 C3/245 dev.cpu.3.cx_lowest: C2 62w idle power John Theus TheUs Group TheUsGroup.com ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: powerd and increase in energy need
Quoting Luigi Rizzo ri...@iet.unipi.it (from Wed, 21 Mar 2012 18:37:28 +0100): I guess that the credit for power saving goes mostly to the CPU architects. Powerd only gives second-order savings, and C1 vs. C3 is ineffective, at least for HZ=1000 CPU Power (watts) freqidle16 threads --- 200 48 51 2200 52 83 3200 54 115 3401 56 118 powerd 48 118 I hope you all don't use a cheap PSU, but a _good_ high efficient one, which really draws less power when idle instead of generating heat. Some PSUs are only efficient in a sweet spot, instead of being efficient over a broad range, even when being idle. See http://en.wikipedia.org/wiki/80_PLUS for a quick and not so in-deep overview (and the reality may differ from manufacturer to manufacturer). Bye, Alexander. -- That does not compute. http://www.Leidinger.netAlexander @ Leidinger.net: PGP ID = B0063FE7 http://www.FreeBSD.org netchild @ FreeBSD.org : PGP ID = 72077137 ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: powerd and increase in energy need
On Thu, Mar 22, 2012 at 10:51 AM, Alexander Leidinger alexan...@leidinger.net wrote: Quoting Luigi Rizzo ri...@iet.unipi.it (from Wed, 21 Mar 2012 18:37:28 +0100): I guess that the credit for power saving goes mostly to the CPU architects. Powerd only gives second-order savings, and C1 vs. C3 is ineffective, at least for HZ=1000 CPU Power (watts) freqidle16 threads --- 200 48 51 2200 52 83 3200 54 115 3401 56 118 powerd 48 118 I hope you all don't use a cheap PSU, but a _good_ high efficient one, which really draws less power when idle instead of generating heat. Some PSUs are only efficient in a sweet spot, instead of being efficient over a broad range, even when being idle. See http://en.wikipedia.org/wiki/** 80_PLUS http://en.wikipedia.org/wiki/80_PLUS for a quick and not so in-deep overview (and the reality may differ from manufacturer to manufacturer). it isn't such a big deal in my opinion. The %efficiency at low levels is misleading if you don't factor out the 5-10W plateau for keeping the PSU alive (fan, ballast, etc.). See for instance http://www.techpowerup.com/reviews/Antec/HCG-520/5.html the table at the end of the page reports 6.73W of idle power. At 40W this PSU consumes 52.9W, so the apparent efficiency is 75%, but factoring out the idle power you go way up. cheers luigi -- That does not compute. http://www.Leidinger.netAlexander @ Leidinger.net: PGP ID = B0063FE7 http://www.FreeBSD.org netchild @ FreeBSD.org : PGP ID = 72077137 -- -+--- Prof. Luigi RIZZO, ri...@iet.unipi.it . Dip. di Ing. dell'Informazione http://www.iet.unipi.it/~luigi/. Universita` di Pisa TEL +39-050-2211611 . via Diotisalvi 2 Mobile +39-338-6809875 . 56122 PISA (Italy) -+--- ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: powerd and increase in energy need
Quoting Luigi Rizzo ri...@iet.unipi.it (from Thu, 22 Mar 2012 14:59:46 +0100): it isn't such a big deal in my opinion. The %efficiency at low levels is misleading if you don't factor out the 5-10W plateau for keeping the PSU alive (fan, ballast, etc.). See for instance My point is: if you (plural) don't see the expected difference between the states or frequency levels, you first have to make sure your PSU is working in a way which allows to see a difference before you can tell that a C-state or a frequency change do not do what you want them to do. Bye, Alexander. -- Murray's Rule: Any country with democratic in the title isn't. http://www.Leidinger.net Alexander @ Leidinger.net: PGP ID = B0063FE7 http://www.FreeBSD.org netchild @ FreeBSD.org : PGP ID = 72077137 ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: powerd and increase in energy need
On Wed, Mar 21, 2012 at 1:00 AM, John j...@theusgroup.com wrote: my zfs nas has an Asus p5e motherboard (x38 chip) and an intel q9300 (quad core 2,5Ghz) processor with all the energy save setting enabled in the bios. Today I connected the power cord to a voltcraft energy meter to see how much energy the whole system needs in idle mode. I found out that with powerd running the cpu get clocked down to 499 mhz with is nice. The funny thing is that this doesn't decrease the amount of watts the machine need. 2,5ghz or 499mhz doen't matter at all. It gets even funnier. With powerd running the systems actually needs 4 watts more then without powerd running. Isn't the whole point of powerd to to decease the energy needs of a machine? or is it utterly broken with this cpu generation? Powerd does decrease energy on my more modern hardware. This machine is used for backups and is idle much of the time. It runs Freebsd 8.3-Prerelease with the turbo-boost patch on an i5-650 in an intel DH55HC motherboard. The following power measurements were made with a Kill-A-Watt meter. 91w while doing a compile, dev.cpu.0.freq: 3193 (turbo boost enabled) 81w compile complete, disks quiet, top reports between 99.9 and 100% idle dev.cpu.0.freq: 3193 71w idle for several seconds, powerd running in hiadaptive mode, dev.cpu.0.freq: 1197 sysctl dev.cpu |grep cx dev.cpu.0.cx_supported: C1/3 C2/205 C3/245 dev.cpu.0.cx_lowest: C2 dev.cpu.0.cx_usage: 100.00% 0.00% 0.00% last 259us sysctl dev.cpu |grep freq ~ dev.cpu.0.freq: 1197 dev.cpu.0.freq_levels: 3193/9875 3192/9125 3059/8250 2926/7500 2793/6875 2660/6250 2527/5750 2394/5250 2261/4750 1197/2750 /etc/rc.conf powerd_flags=-n hadp performance_cx_lowest=C2 economy_cx_lowest=C2 performance_cpu_freq=HIGH John Theus TheUs Group TheUsGroup.com I will give these setting a try thx.. ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: powerd and increase in energy need
On Wed, Mar 21, 2012 at 12:41 AM, Matthias Gamsjager mgamsja...@gmail.com wrote: On Wed, Mar 21, 2012 at 1:00 AM, John j...@theusgroup.com wrote: my zfs nas has an Asus p5e motherboard (x38 chip) and an intel q9300 (quad core 2,5Ghz) processor with all the energy save setting enabled in the bios. Today I connected the power cord to a voltcraft energy meter to see how much energy the whole system needs in idle mode. I found out that with powerd running the cpu get clocked down to 499 mhz with is nice. The funny thing is that this doesn't decrease the amount of watts the machine need. 2,5ghz or 499mhz doen't matter at all. It gets even funnier. With powerd running the systems actually needs 4 watts more then without powerd running. Isn't the whole point of powerd to to decease the energy needs of a machine? or is it utterly broken with this cpu generation? Powerd does decrease energy on my more modern hardware. This machine is used for backups and is idle much of the time. It runs Freebsd 8.3-Prerelease with the turbo-boost patch on an i5-650 in an intel DH55HC motherboard. The following power measurements were made with a Kill-A-Watt meter. 91w while doing a compile, dev.cpu.0.freq: 3193 (turbo boost enabled) 81w compile complete, disks quiet, top reports between 99.9 and 100% idle dev.cpu.0.freq: 3193 71w idle for several seconds, powerd running in hiadaptive mode, dev.cpu.0.freq: 1197 sysctl dev.cpu |grep cx dev.cpu.0.cx_supported: C1/3 C2/205 C3/245 dev.cpu.0.cx_lowest: C2 dev.cpu.0.cx_usage: 100.00% 0.00% 0.00% last 259us sysctl dev.cpu |grep freq ~ dev.cpu.0.freq: 1197 dev.cpu.0.freq_levels: 3193/9875 3192/9125 3059/8250 2926/7500 2793/6875 2660/6250 2527/5750 2394/5250 2261/4750 1197/2750 /etc/rc.conf powerd_flags=-n hadp performance_cx_lowest=C2 economy_cx_lowest=C2 performance_cpu_freq=HIGH John Theus TheUs Group TheUsGroup.com I will give these setting a try thx.. If you are trying to reduce power consumption, why are you limiting Cx states to C2 (which save little) and not C3 (which will save a LOT of power when the CPU is not heavily loaded). If it is due to the system hanging, it is almost certainly because you have throttling enabled. Throttling, either by the use of TCC (also called P4TCC) or the older, externally implemented throttling mechanism, is a BAD BAD THING! I have complained for years about it being the default. It is intended for thermal control, not power management. The power savings will be negligible and, in combination with deep sleep modes (Cx 2) can and do result in the CPU going into deep sleep and never waking up. You can (and should) disable them in /boot/loader.conf with: # Disable CPU throttling hint.p4tcc.0.disabled=1 hint.acpi_throttle.0.disabled=1 This should greatly reduce the large number of frequencies available, but they will be the ones provided by EST.which really do reduce power consumption. (I put frequencies in quotation marks because throttling does not really change the clock speed. It simply skips 'N' of every 8 clock cycles. Still, compared to C3 and higher, EST is a minor power savings. Just following the recommendations on the power management web page is the way to go. -- R. Kevin Oberman, Network Engineer E-mail: kob6...@gmail.com ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: powerd and increase in energy need
2012/3/21 Kevin Oberman kob6...@gmail.com: If you are trying to reduce power consumption, why are you limiting Cx states to C2 (which save little) and not C3 (which will save a LOT of power when the CPU is not heavily loaded). Jumping up on this but I don't know if that's related to his reasons to not use C3. Mine are simple : # sysctl dev.cpu | grep temperature dev.cpu.0.temperature: 39,0C dev.cpu.1.temperature: 40,0C dev.cpu.2.temperature: 36,0C dev.cpu.3.temperature: 36,0C dev.cpu.4.temperature: 41,0C dev.cpu.5.temperature: 41,0C dev.cpu.6.temperature: 36,0C dev.cpu.7.temperature: 36,0C # sysctl hw.acpi.cpu.cx_lowest=C3 hw.acpi.cpu.cx_lowest: C2 - C3 # sysctl dev.cpu | grep temperature dev.cpu.0.temperature: 44,0C dev.cpu.1.temperature: 44,0C dev.cpu.2.temperature: 40,0C dev.cpu.3.temperature: 40,0C dev.cpu.4.temperature: 46,0C dev.cpu.5.temperature: 46,0C dev.cpu.6.temperature: 41,0C dev.cpu.7.temperature: 41,0C # sysctl hw.acpi.cpu.cx_lowest=C2 hw.acpi.cpu.cx_lowest: C3 - C2 # sysctl dev.cpu | grep temperature dev.cpu.0.temperature: 40,0C dev.cpu.1.temperature: 40,0C dev.cpu.2.temperature: 36,0C dev.cpu.3.temperature: 36,0C dev.cpu.4.temperature: 42,0C dev.cpu.5.temperature: 42,0C dev.cpu.6.temperature: 36,0C dev.cpu.7.temperature: 36,0C Only 1-2 seconds between each command, no current load. As you can see, when I engage C3 states, the CPU temperature increases by 4-5°C. I expected it to drop. This is with : # sysctl dev.cpu | grep freq dev.cpu.0.freq: 2933 dev.cpu.0.freq_levels: 2933/95 2799/95 2266/75 1733/56 1199/39 # grep perf /etc/rc.conf performance_cx_lowest=C2 performance_cpu_freq=HIGH # grep hint /boot/loader.conf hint.p4tcc.0.disabled=1 hint.acpi_throttle.0.disabled=1 # dmesg | head -n 13 | tail -n 9 FreeBSD 9.0-STABLE #0 r233000M: Thu Mar 15 12:30:27 CET 2012 r...@zozo.afpicl.lan:/usr/obj/usr/src/sys/CORE amd64 CPU: Intel(R) Core(TM) i7 CPU 860 @ 2.80GHz (2793.04-MHz K8-class CPU) Origin = GenuineIntel Id = 0x106e5 Family = 6 Model = 1e Stepping = 5 Features=0xbfebfbffFPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE Features2=0x98e3fdSSE3,DTES64,MON,DS_CPL,VMX,SMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,SSE4.1,SSE4.2,POPCNT AMD Features=0x28100800SYSCALL,NX,RDTSCP,LM AMD Features2=0x1LAHF TSC: P-state invariant, performance statistics I tried with and without powerd and there's no noticeable difference, so I don't use it. I also tried with and without performance_cpu_freq=HIGH in /etc/rc.conf (without, dev.cpu.0.freq is 2799 so I don't think TurboBoost is enabled in this case). If it is due to the system hanging, it is almost certainly because you have throttling enabled. Throttling, either by the use of TCC (also called P4TCC) or the older, externally implemented throttling mechanism, is a BAD BAD THING! I have complained for years about it being the default. It is intended for thermal control, not power management. The power savings will be negligible and, in combination with deep sleep modes (Cx 2) can and do result in the CPU going into deep sleep and never waking up. You can (and should) disable them in /boot/loader.conf with: # Disable CPU throttling hint.p4tcc.0.disabled=1 hint.acpi_throttle.0.disabled=1 This should greatly reduce the large number of frequencies available, but they will be the ones provided by EST.which really do reduce power consumption. (I put frequencies in quotation marks because throttling does not really change the clock speed. It simply skips 'N' of every 8 clock cycles. Still, compared to C3 and higher, EST is a minor power savings. Just following the recommendations on the power management web page is the way to go. -- R. Kevin Oberman, Network Engineer E-mail: kob6...@gmail.com ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org -- Olivier Smedts _ ASCII ribbon campaign ( ) e-mail: oliv...@gid0.org - against HTML email vCards X www: http://www.gid0.org - against proprietary attachments / \ Il y a seulement 10 sortes de gens dans le monde : ceux qui comprennent le binaire, et ceux qui ne le comprennent pas. ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: powerd and increase in energy need
On Wed, Mar 21, 2012 at 09:32:47AM -0700, Kevin Oberman wrote: ... If you are trying to reduce power consumption, why are you limiting Cx states to C2 (which save little) and not C3 (which will save a LOT of power when the CPU is not heavily loaded). If it is due to the system hanging, it is almost certainly because you have throttling enabled. Throttling, either by the use of TCC (also called P4TCC) or the older, externally implemented throttling mechanism, is a BAD BAD THING! I have complained for years about it being the default. It is intended for thermal control, not power management. The power savings will be negligible and, in combination with deep sleep modes (Cx 2) can and do result in the CPU going into deep sleep and never waking up. You can (and should) disable them in /boot/loader.conf with: # Disable CPU throttling hint.p4tcc.0.disabled=1 hint.acpi_throttle.0.disabled=1 This should greatly reduce the large number of frequencies available, but they will be the ones provided by EST.which really do reduce power consumption. (I put frequencies in quotation marks because throttling does not really change the clock speed. It simply skips 'N' of every 8 clock cycles. Still, compared to C3 and higher, EST is a minor power savings. interesting. Can you elaborate on that ? This is one of my new machines, hw.model: Intel(R) Core(TM) i7-2600K CPU @ 3.40GHz dev.cpu.0.%desc: ACPI CPU dev.cpu.0.%driver: cpu dev.cpu.0.%location: handle=\_PR_.P000 dev.cpu.0.%pnpinfo: _HID=none _UID=0 dev.cpu.0.%parent: acpi0 dev.cpu.0.freq: 600 dev.cpu.0.freq_levels: 3401/255000 3300/245000 3200/236000 3100/227000 3000/218000 2900/209000 2800/20 2700/192000 2600/183000 2500/175000 2400/167000 2300/159000 2200/151000 2100/143000 1837/125125 1600/87000 1400/76125 1200/65250 1000/54375 800/43500 600/32625 400/21750 200/10875 dev.cpu.0.cx_supported: C1/1 C2/80 C3/104 dev.cpu.0.cx_lowest: C1 dev.cpu.0.cx_usage: 100.00% 0.00% 0.00% last 210us Here using C1 or C3 does not seem to make any difference at all in terms of power (measured with a Kill-a-watt style wattmeter), and irrespective of the frequency setting the idle power does not change much (48..56W across the entire range). This is on FreeBSD 9 with HZ=1000, maybe some marginal savings can be achieved setting HZ=100 (at some point i will give it a try). Under heavy load (16 threads running infinite loops across the 4 cores) the power goes up as expected (up to 118W for 4 cores, 76W using just 1 core), and powerd seems to do a decent job in keeping the idle power low. I guess that the credit for power saving goes mostly to the CPU architects. Powerd only gives second-order savings, and C1 vs. C3 is ineffective, at least for HZ=1000 CPU Power (watts) freqidle16 threads --- 200 48 51 2200 52 83 3200 54 115 3401 56 118 powerd 48 118 cheers luigi ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: powerd and increase in energy need
On Tue, Mar 20, 2012 at 3:41 PM, Matthias Gamsjager mgamsja...@gmail.com wrote: Hi, my zfs nas has an Asus p5e motherboard (x38 chip) and an intel q9300 (quad core 2,5Ghz) processor with all the energy save setting enabled in the bios. Today I connected the power cord to a voltcraft energy meter to see how much energy the whole system needs in idle mode. I found out that with powerd running the cpu get clocked down to 499 mhz with is nice. The funny thing is that this doesn't decrease the amount of watts the machine need. 2,5ghz or 499mhz doen't matter at all. It gets even funnier. With powerd running the systems actually needs 4 watts more then without powerd running. Isn't the whole point of powerd to to decease the energy needs of a machine? or is it utterly broken with this cpu generation? You probably want to check out the following article on the FreeBSD wiki: http://wiki.freebsd.org/TuningPowerConsumption The low-power states should be available to you after following the configuration guide. -Brandon ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: powerd and increase in energy need
my zfs nas has an Asus p5e motherboard (x38 chip) and an intel q9300 (quad core 2,5Ghz) processor with all the energy save setting enabled in the bios. Today I connected the power cord to a voltcraft energy meter to see how much energy the whole system needs in idle mode. I found out that with powerd running the cpu get clocked down to 499 mhz with is nice. The funny thing is that this doesn't decrease the amount of watts the machine need. 2,5ghz or 499mhz doen't matter at all. It gets even funnier. With powerd running the systems actually needs 4 watts more then without powerd running. Isn't the whole point of powerd to to decease the energy needs of a machine? or is it utterly broken with this cpu generation? Powerd does decrease energy on my more modern hardware. This machine is used for backups and is idle much of the time. It runs Freebsd 8.3-Prerelease with the turbo-boost patch on an i5-650 in an intel DH55HC motherboard. The following power measurements were made with a Kill-A-Watt meter. 91w while doing a compile, dev.cpu.0.freq: 3193 (turbo boost enabled) 81w compile complete, disks quiet, top reports between 99.9 and 100% idle dev.cpu.0.freq: 3193 71w idle for several seconds, powerd running in hiadaptive mode, dev.cpu.0.freq: 1197 sysctl dev.cpu |grep cx dev.cpu.0.cx_supported: C1/3 C2/205 C3/245 dev.cpu.0.cx_lowest: C2 dev.cpu.0.cx_usage: 100.00% 0.00% 0.00% last 259us sysctl dev.cpu |grep freq ~ dev.cpu.0.freq: 1197 dev.cpu.0.freq_levels: 3193/9875 3192/9125 3059/8250 2926/7500 2793/6875 2660/6250 2527/5750 2394/5250 2261/4750 1197/2750 /etc/rc.conf powerd_flags=-n hadp performance_cx_lowest=C2 economy_cx_lowest=C2 performance_cpu_freq=HIGH John Theus TheUs Group TheUsGroup.com ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
