Petabyte Pi Part 2

General Chia Discussion
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For anyone interested in using a low power draw harvester, this video might be of interest.

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Interesting, but if I was running that much storage I would want it running off something better. The mATX motherboard on my GPU mining rig draws about 17w, when running 60 drives thats negligible.

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I agree.

But you could run three Pi’s, and have three harvesters, and avoid living on the limits of the hardware.

With that video, you know where the breaking points are.

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But then you would have three things to maintain and upgrade, space and cabling.

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Your storage drives need to be plugged into a computer, one way or another.

The reason that I posted that video is for someone looking for a low power solution, without having to figure out the Pi’s stability thresholds.

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Yeah, I am also drooling seeing that enclosure. Although, I would like him to provide more info on two things (enclosure related):

  1. Why that box draws ~500 W when those drives are in idle state. Those are Seagate 20 TB that in idle should draw ~5.4 W in idle per Seagate data sheet (~320 W drives + 50-100 W the rest). So, he should really run smartctl to get power states of those drives. Also, it is really easy for SAS/SATA controlled newer (maybe x16+) Seagate drives to force them to IDLE_A state (potentially lower power draw than in just IDLE, maybe around 3.5 W only). Although maybe btrfs is keeping those drives in active state.
  2. What are the temps of those drives (as above IDLE_A is the desired power state).

I also agree with @Ronski that with so many drives, whether the CM4 takes 10W or a low power board 20-30W, it really doesn’t matter with that many drives, thus a low power mb would be a much better solution (if not just for a full speed SATA and no headaches he described, as no Broadcom engineer will support any of us). It may be that more power saving can be achieved by using some low power HBAs or expanders (say 1-2 W per port ranges) rather than focusing on the mobo / CPU. Also, factoring in price / availability of CM4 boards, it could be equal or less expensive to go that low power PC route, plus it can be purchased today, not some sort of a pre-paid deal that may eventually go through when Santa comes.

Although, I really did stop drooling when he stated the price. Looking at Storinator page, that enclosure runs around $10k (if can be purchased bare bones at all). One can buy on eBay Netapp 24 drives enclosure for $330, so 72 drive bay for just one grand. Those enclosures will have much better temps control but may draw a bit more power. That implies that for the price of that Storinator that holds 1.1 PB, one can buy 30 such Netapp enclosures holding 14.4 PB. Yeah, that is the end of my drooling, and realizing that the video was more like a paid add by Storinator in his otherwise superb YT channel.

Still, for those that are currently running RPis, this is really a good video about how to dump USB headaches, and switch to SATA (regardless of what will be used as an enclosure). Based on his early work on that, the SATA support was added to RPi OSes. Actually, I posted about it long time ago, when Jeff had his first videos about using PCIe interface to hold single HBAs.

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