Speaking of AGCs, he just recently uploaded a video where they used a restored AGC to dump prototype core rope memory modules from the Computer History Museum's (non-functional) AGC.

Repeated hashing is notoriously difficult to parallelize as it's naturally a serial operation, that's why we use repeated hashing as a Key-Derivative Function to protect passwords. For humans it's more challenging, since SHA-256 has 64 rounds internally, which means: to calculate a single hash, you need to iterate over the data 64 times, each time using the output of the previous round as your input.

What you can do, is:

(1) Optimizing the process of calculating a single round. I guess you can identify all the needed arithmetic steps (mostly logical opeartions and bitshifts) and divide them to multiple units of task-forces, assembly-line style, like a human-powered ALU. Ideally, workers that doesn't care about "which round it is", but only care about the computation itself should be as many as possible, i.e. using combinational logic instead of sequential logic.

I think many computations were done in this way before electronic computers, I believe even numerical simulations of fluid dynamics were done by rooms of female workers with mechanical computers running the same algorithm again and again over a matrix.

(2) Create as many copies of your human-ALU as possible. Although iterations within a single-hashing operation is not parallelized. But mining only requires you to do independent hashing, so it should scale linearly.

I don't have the needed skills to get an actual number, if you - the reader, thinks you can. Please do it and submit your blogpost to Hacker News.

And I wasn't interested so much in the absolute throughput, but how the figure would change in terms of hashes per second per human, so duplicating a full ALU module wouldn't be relevant; the concern is how much an additional human improves the rate after adjusting for the fact that you added one more human-resource.

Edit: I'm new to queuing theory, but I may just grind through the numbers there. Could do it as a "Show HN" if there is a tool (preferably as a web app) where you can model a process and tweak the numbers like in Factorio.

> Right, I was mainly thinking in terms of speedups from not having to switch tasks and the gains from specializing in one kind of computation.

Switching tasks is going to be a relatively small amount of time over a 24 hr period. Given that one person can only hash 0.67 hashes per day assuming full undivided attention I'm really not sure what you could count on saving.

The biggest advantage adding more people would do would make it actually feasible to calculate continuously as I doubt any human has the focus/patience for doing mundane number crunching for 24 hours without breaks.

I totally get that this is all hypothetical-for-fun math, obviously nobody is going to actually try to mine bitcoin by hand. But that 0.67 hashes per day is terribly low, a 50% speed improvement would only barely put you over 1h/d. Not to mention we normally compare in h/s not h/d so it's actually 7.75e-6 H/s.

I wonder if you can do these on that old HP calculator everybody loved (the 48, I think?) and how fast.