Hardware Sizing & Throughput Considerations
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You could find also next opportunity: Diagnostics:Command prompt, run```
sysctl -a | grep cputhen you should find next kind text``` dev.cpu.0.freq: 3000Then you can go to /boot/loader.conf.local and create a line with a smaller frequency, like 200.
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Powerd should take care of all that for you. It depends which driver it's using though. It's only really effective when it uses a driver that can scale back the voltage as well as frequency. I'm not sure FreeBSD will have caught up with i5 yet.
Steve
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The graphs at that link are quite revealing. Those desktop Atoms have no powersaving features. Look at the D510, 28W at 0 load, 33W at 100% load. :o The Netbook atoms are much better <10W at idle.
Steve
Yeah, for some reason they didn't include speedstep in the desktop versions, so they run at full power all the time. It's another reason I went with the i3 instead.
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@Bai:
It's another reason I went with the i3 instead.
Good choice! :)
It must have been a marketing decision. To differentiate between the two cpus. Same as Pentium-M vs Celeron-M.Steve
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I undervolted everything on the CPU a couple of days back. It has bought down my idle CPU temperature from 60C to 55C. The enclosure is much less warm than before. Undervolting the CPU hasn't impacted performance, though the CPU runs around 15 to 20% on heavy downloads. Glad it's working without problems till now.
Intel(R) Core(TM) i5-2500K CPU @ 3.30GHz
Current: 200 MHz, Max: 1600 MHzSpeed bumps from 200/400 to 800/1200 frequently, Powerd in action?
Should I undervolt the RAM too? If yes, will that impact the performance? Bumping my 4GB RAM to 8GB this week.. need it for Snort and Squid.
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I take it you are manually undervolting in the bios?
This usually only leads to instability. There will be some room for adjustment as the recommended voltage will be well within the tolerance on the cpu. If, say, you keep adjusting the voltage down what will happen is that you will reach a level at which the CPU starts making calculation errors at it's maximum frequency. The trouble is that with powerd enabled and such a fast cpu it will hardly ever run at maximum frequency.
If you are serious about reducing the voltage you need to run a stress test on the cpu to ensure it's stable.
Undervolting the ram will make almost no difference to power consumption or cpu temperature, I wouldn't bother.
Does your i5 have any speedstep like powersaving modes? I haven't looked into it.Steve
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Yes, I did the undervolting from the BIOS. Set the lowest possible value for all CPU settings along with the multiplier. Don't think pfSense can put this CPU into any kind of decent stress unless I have a Gigabit WAN bandwidth.. lol.
Do you recommend I switch back to the original BIOS settings and let powerd do the job?
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It depends what powerd is doing, which depends on what driver it's using to control the cpu. Generally speaking using some sort of dynamic frequency/voltage control, like powerd, is a much better solution since it still gives you access to higher cpu powers if you need them.
Here are some results I had when testing my own box, a Pentium-M with enhanced speedstep.[2.0-BETA4][root@pfSense.localdomain]/root(12): sysctl dev.cpu.0.freq=1500 dev.cpu.0.freq: 600 -> 1500 [2.0-BETA4][root@pfSense.localdomain]/root(13): mbmon ioctl(smb0:open): No such file or directory Temp.= 25.0, 32.0, 0.0; Rot.= 10384, 10546, 9375 Vcore = 1.33, 2.13; Volt. = 3.39, 5.13, 12.40, -12.28, -2.13 [2.0-BETA4][root@pfSense.localdomain]/root(14): sysctl dev.cpu.0.freq=600 dev.cpu.0.freq: 1500 -> 600 [2.0-BETA4][root@pfSense.localdomain]/root(15): mbmon ioctl(smb0:open): No such file or directory Temp.= 25.0, 31.0, 0.0; Rot.= 10384, 10384, 9375 Vcore = 0.96, 2.08; Volt. = 3.39, 5.13, 12.40, -12.28, -2.13 [2.0-BETA4][root@pfSense.localdomain]/root(10): sysctl dev.cpu.0.freq_levels dev.cpu.0.freq_levels: 1500/-1 1200/-1 1000/-1 800/-1 600/-1The cpu voltage is dropped a lot but only at low frequencies. See here for more details.
There are a number of packages available in FreeBSD to load the CPU, I used cpuburn.Steve
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@Bai:
It's another reason I went with the i3 instead.
Good choice! :)
It must have been a marketing decision. To differentiate between the two cpus. Same as Pentium-M vs Celeron-M.Steve
Well, it'd be a better choice if I could find a power supply smaller than 400W. I'm using a 430W I had laying around, but it's way overkill for the machine.
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So I increased my bandwidth this week to 50/8. The entire bandwidth is hogged up by users who are really excited with the extra speed. I see my CPU take a beating since I lowered it's voltage down to a 1600Mhz. Thinking about switching it back to defaults and let Powerd handle the frequency.
Any suggestions?
