tests hang when changing jubjub to n=3

initc3 / HoneyBadgerMPC

Robust MPC-based confidentiality layer for blockchains

GNU General Public License v3.0

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tests hang when changing jubjub to n=3 #264

Closed amiller closed 5 years ago

amiller commented 5 years ago

I think @Drake-Eidukas is already looking into this, creating an issue just to keep track of it:

https://github.com/initc3/HoneyBadgerMPC/tree/n4-error-mask
https://github.com/initc3/HoneyBadgerMPC/pull/262 As far as I can tell, the problem is suppressed by changing the tests in tests/progs/test_jubjub.py from n=3 to n=4. Both of the erroring branches above are with n=3. But there's no good reason why this should be the case. What could be going wrong?

Drake-Eidukas commented 5 years ago

So, when I was initially working with jubjub, @smkuls mentioned that these tests are way more stable / aren't getting stuck when n, t = 4, 1 (n = 3t + 1), because it expects more points which it's not getting.

I've yet to figure this out but I'm going to look into it more now

Drake-Eidukas commented 5 years ago

Do you think this has to do with the fact that the Equality mixin for shares utilizes ShareArray, and when using share arrays, it calls upon batch_reconstruct for opening? According to the docs, it needs that n >= 3t + 1. Not sure if this would cause this behaviour with hanging, but it's the best I came up with. Jubjub is the only user of Equality I know of.

amiller commented 5 years ago

I'm closing this because I can no longer reproduce it. With the current dev branch d8a9c4a even setting this to n=3 the tests all pass