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Saving Energy: Home Server That Automatically Suspends to RAM and Wakes Up Again

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Re: Saving Energy: Home Server That Automatically Suspends to RAM and Wakes Up Again

#93
I was using hdparm on my rpi home server to turn off the disk without unmounting it.

It was just a cronjob to turn it off at night, and it would stay off until needed.

The first request would then take over 5 seconds to turn it on again, and it would remain on.

Re: Saving Energy: Home Server That Automatically Suspends to RAM and Wakes Up Again

#94

Smartphones can be connected for days on the internal battery, using well under a watt, and they can be ready to respond instantly, and they have an app container system that makes everything just work. I really think we need to start making Android servers a thing, at least for self hosting, maybe for everything. Judging by how WearOS seems to be able to run on 35mA or less, I think there's a good case for just maki…

The power saving is not because of Android it is because of the ARM arch being used under the hood. And ARM servers for power saving purposes are very much a thing already.

> The power saving is not because of Android it is because of the ARM arch being used under the hood.

[citation needed]

Based on my understanding, the underlying OS has way more to do with power usage than the instruction set, and AFAIK Android has tons of optimizations specifically geared towards reducing battery consumption (and therefore power usage) on mobile devices.

With that said, it's true that, in practice, the power floor seems to be lower for ARM devices than, say, x86, but I'd wager that this has far more to do with target market than with ARM's instruction set. Low power x86 boards do (did?) exist.

Re: Saving Energy: Home Server That Automatically Suspends to RAM and Wakes Up Again

#95

Earlier quoted context omitted.

Or the energy usage of Germany’s chemicals industry…

Or the cost of running water pumps for public fountains

The romans had water fountains and no pumps.

Perhaps you underestimate gravity.

Re: Saving Energy: Home Server That Automatically Suspends to RAM and Wakes Up Again

#96
post #85

You don't even need magic packets from a dedicated machine for wake on lan for some NIC's. For example on linux using `ethtool -s enp3s0 wol pug` will wake the system on p (PHY activity), u (unicast activity) and g (magic packet activity). Of course this is entirely dependent on how "noisy" your network is. This is something I've been thinking about for some time as I'm working on re-building my homelab for a more po…

I've been shutting off my hard drives but found that anything short of unmounting them caused them to be awoken frequently by random processes with timer-based disk access. My solution was to move all my online use-cases to a separate SSD and mount the HDDs only when I need them for a manual process. E.g. when I want to watch a movie I have downloaded, I'll mount the disk pool and copy it to the SSD (although my inte…

I was doing it and it worked fine. But I'd just keep the served content on the disk. Of course not /var.

Re: Saving Energy: Home Server That Automatically Suspends to RAM and Wakes Up Again

#97

If you're penny pinching also have a look at your network equipment. As a test I set all switch ports on my 24 port HP from 1Gbps to 100Mbps and the power usage dropped by 10W. About half the ports on the switch are occupied. But then again, with the current prices it might make more sense just to replace the hardware with a newer more efficient model and it will pay itself back in a year instead of 5.

This is an example of where getting rid of old kit & replacing it with new more power efficient hardware ends up being the greener option.

Re: Saving Energy: Home Server That Automatically Suspends to RAM and Wakes Up Again

#98
If you want to push energy efficiency the Raspberry 2 (old ARM v7 version) is the best device at 1W idle / 2W full load, it saturates the SD card. One step up is Raspberry 4 for heavier workloads/networking at 3W idle / 6W full load, and after that 8-core Atom at 15W idle / 25W full load.

As mentioned elsewhere in this thread, 100Mb/s, vs 1Gb/s vs 10Gb/s makes a lot of difference. IMO 1Gb/s is the only reasonable speed for home hosting as to saturate 10Gb/s you would need at least 20x (50Ah) lead-acid batteries of backup and that is almost industrial levels of investment/maintenance.

The final constraint is that disks and RAM uses more energy than you would think, 256GB DDR5 uses 80W! And they wear faster than you would think too at these nm! Be careful with writes!

So you need to plan your structure with the proper redundancy without going to far above the previously mentioned 1Gb/s saturation for your particular applications.

Re: Saving Energy: Home Server That Automatically Suspends to RAM and Wakes Up Again

#99

Smartphones can be connected for days on the internal battery, using well under a watt, and they can be ready to respond instantly, and they have an app container system that makes everything just work. I really think we need to start making Android servers a thing, at least for self hosting, maybe for everything. Judging by how WearOS seems to be able to run on 35mA or less, I think there's a good case for just maki…

but Android is just based on Linux, so in theory you could tweak a regular Linux server on ARM hardware to get good energy efficiency. The downside of Android is its reliance on Java, which adds a lot of overhead compared to bare-metal languages (I strongly believe - but have no sources or figures to back this up - this is why Apple phones have been faster and more energy efficient, especially in the earlier days (think iphone 4 and co)

Re: Saving Energy: Home Server That Automatically Suspends to RAM and Wakes Up Again

#100
Something's not right.

I own both a passively cooled 2016 Mini PC OLOEY Intel Core i7-7500U (as a home media center) and a 2023 Minisforum UM690 (for work and it's amazing btw), and they both use about 7 watts when idling (screen off).

How op is using 43 watts for an idling media center is just beyond me, he must be using a 1978 Intel 8086, right?

Anyhow, 4 watts is still far better than 7 watts and this is a great achievement, but those 43 watts are really sketchy imho.

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