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Show HN: Terminal dashboard that throttles my PC during peak electricity rates

naveen.ing

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Re: Show HN: Terminal dashboard that throttles my PC during peak electricity rates

#41

Post by naveen_k »

KennyBlanken wrote: post #25
russdill wrote: post #11

If your computer is still doing bursty jobs during that period, it will use less power but still as much energy. Sure, you can reduce the power but if you aren't also reducing what you ask it to do, it'll just use that max amount of allowed power for a longer period of time.

It is well known in the PC hardware enthusiast community that the last few digits of percent of performance come at enormous increases in power consumption as voltages are raised to prevent errors as clock speeds go up. Manufacturers chase benchmark results by youtubers and magazines. Even a few percent difference in framerate means the difference between everyone telling each other to buy a particular motherboard, p…

I'm actually using a 1600W PSU. 1400W is my target max draw. This is a dual EPYC (64 core CPU each) system btw. The max draw by the CPU+MB+Drives running at peak 3700MHz without the GPU is 495W! Adding 4x 4090 (underclocked) will quickly get you to 1400W+.

Re: Show HN: Terminal dashboard that throttles my PC during peak electricity rates

#42

Post by naveen_k »

creaturemachine wrote: post #38
KennyBlanken wrote: post #25

Earlier quoted context omitted.

It is well known in the PC hardware enthusiast community that the last few digits of percent of performance come at enormous increases in power consumption as voltages are raised to prevent errors as clock speeds go up. Manufacturers chase benchmark results by youtubers and magazines. Even a few percent difference in framerate means the difference between everyone telling each other to buy a particular motherboard, p…

1400 is definitely the sticker on the side of the PSU. There is some theory behind keeping your PSU at 30-50% for optimal efficiency, but considering the cost of these 1k+ W units You're probably better off right-sizing it.

It's a 1600W PSU (Coolmaster 1600 V2 Platinum)

Re: Show HN: Terminal dashboard that throttles my PC during peak electricity rates

#43

Post by PaulKeeble »

wongarsu wrote: post #28
delusional wrote: post #17

Earlier quoted context omitted.

This is some pretty old analysis, but I remember when smartphones came out and people were thinking about throttling their applications to lower power consumption the general advice was to just "race to idle". The consensus thus was that spending more time in lower power states (where you use ~0W) was much more efficient than spending a longer amount of time in the CPU sweetspot, but with all sort of peripherals onli…

However there are two factors that might make "race to idle" more valid on phones than on most other platforms: Smartphone chips are designed to much stricter thermal and power limits. There is only so much power you can get out of the tiny battery, and only so much heat you can get rid of without making the phone uncomfortably hot. Even in a burst that puts a limit on the wastefulness. Desktop CPUs are very differen…

The thing is all these phones are also coming with 2 or 3 different classes of CPUs in order to save power, those slower cores must be achieving much better Watts per Op otherwise they wouldn't bother and be using all that die space for the faster cores. Clearly they are not doing race to idle in most mobile phones either at this point given they have been using a big/little strategy for over a decade.

What has happened is they realised waking up CPUs to do individual tasks was inefficient and stopped CPUs sleeping so they batched work together but that is basically the overhead of going in and out of sleeping which presumably does waste a bunch of power. This also explains why so many high end phones now have 1 ultra slow core that deals with the background stuff when the phone screen is off, the rest can all just sleep and this low power core can sit there on low clocks sipping minimal power most of the time.

Re: Show HN: Terminal dashboard that throttles my PC during peak electricity rates

#44

Post by ac29 »

KennyBlanken wrote: post #33
naveen_k wrote: post #22

Earlier quoted context omitted.

Thanks! That's an excellent point. You're right that there's likely a sweet spot that would be more efficient overall than aggressive throttling. The current implementation uniformly sets max frequency for all 128 cores, but I'm working on per-core frequency control that would allow much more granular optimization. I'll definitely measure aggregate consumption with your suggestion versus my current implementation to…

Please go learn about modern Ryzen power and performance management, namely Precision Boost Overdrive and Curve Optimizer - and how to undervolt an AM4/AM5 processor. The stuff the chip and motherboard do, completely built-in, is light-years ahead of what you're doing. Your power-saving techniques (capping max frequency) are more than a decade out of date. You'll get better performance and power savings to boot.

For people with Intel processors, check out raplcap: https://github.com/powercap/raplcap

It lets you set specific power consumption limits in W instead of attempting to do the same by restricting maximum core frequencies (which could also be useful in addition to overall power limits).

Re: Show HN: Terminal dashboard that throttles my PC during peak electricity rates

#45

Post by PeterStuer »

KennyBlanken wrote: post #25
russdill wrote: post #11

If your computer is still doing bursty jobs during that period, it will use less power but still as much energy. Sure, you can reduce the power but if you aren't also reducing what you ask it to do, it'll just use that max amount of allowed power for a longer period of time.

It is well known in the PC hardware enthusiast community that the last few digits of percent of performance come at enormous increases in power consumption as voltages are raised to prevent errors as clock speeds go up. Manufacturers chase benchmark results by youtubers and magazines. Even a few percent difference in framerate means the difference between everyone telling each other to buy a particular motherboard, p…

I myself massively overspec my PSU's for my builds as I want ti keep them in the optimal efficiency range rather than pushing their limits. For a typical 800W budget I usually go with a tier1 1200W offering.

Re: Show HN: Terminal dashboard that throttles my PC during peak electricity rates

#46

Post by jorvi »

wongarsu wrote: post #28
delusional wrote: post #17

Earlier quoted context omitted.

This is some pretty old analysis, but I remember when smartphones came out and people were thinking about throttling their applications to lower power consumption the general advice was to just "race to idle". The consensus thus was that spending more time in lower power states (where you use ~0W) was much more efficient than spending a longer amount of time in the CPU sweetspot, but with all sort of peripherals onli…

However there are two factors that might make "race to idle" more valid on phones than on most other platforms: Smartphone chips are designed to much stricter thermal and power limits. There is only so much power you can get out of the tiny battery, and only so much heat you can get rid of without making the phone uncomfortably hot. Even in a burst that puts a limit on the wastefulness. Desktop CPUs are very differen…

> Desktop CPUs are very different: If you can get 10% more performance while doubling power draw, people will just buy bigger coolers and bigger power supplies to go along with the CPU.

No they won't. OEMs will do that to put the 10% higher number on the box ('OC edition!'), but undervolting / powerlimiting has become increasingly popular. Taking a 2-5% haircut on clock frequency lets you reduce power draw by 20-50% for a 1-3% haircut in performance. Suddenly your CPU and GPU are whisper quiet on aircooling.

Re: Show HN: Terminal dashboard that throttles my PC during peak electricity rates

#48

Post by gorbypark »

Pretty neat! I’m currently working on a project that uses an ESP-C6 that just exposes a “switch” over matter/thread thats based off the results from the Spanish electricity prices API. The idea is have the switch be on when it’s one of the cheapest hours of the day, and off otherwise. Then other automations can be based on it. This was pretty trivial to do in home assistant but I want something that’s ultra low power and can just be completely independent of anything for less technical users. My end goal is to have a small battery powered device that wakes up from deep sleep once a day to check the day ahead prices via WiFi. The C6 might be overkill for this, but once I have a proof of concept working I’ll try and pick something that’s ultra low super ultra low power. Something that needs charging once or twice a year would be ideal.

The ideal form factor might be a smart plug itself, but I can’t find any with hackable firmware and also matter/thread/wifi.

Re: Show HN: Terminal dashboard that throttles my PC during peak electricity rates

#49

Post by dartos »

dylan604 wrote: post #27
dartos wrote: post #20

Earlier quoted context omitted.

Yeah I don’t see anything that even suggests it throttles the PC. Looks like it’s just a display.

You mean like the title of the submission suggestion of it throttling?

I meant in the code……… obviously…

Re: Show HN: Terminal dashboard that throttles my PC during peak electricity rates

#50

Post by naveen_k »

gorbypark wrote: post #48

Pretty neat! I’m currently working on a project that uses an ESP-C6 that just exposes a “switch” over matter/thread thats based off the results from the Spanish electricity prices API. The idea is have the switch be on when it’s one of the cheapest hours of the day, and off otherwise. Then other automations can be based on it. This was pretty trivial to do in home assistant but I want something that’s ultra low power…

That's actually pretty cool. ESPs are awesome little things.
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