Quote from: David Rabahy on March 09, 2016, 05:19:51 PM

Quote from: adamstgBit on March 09, 2016, 05:00:29 PM

I assume hardware is always getting better because HELLO! and libsecp256k1 offers 5x validation speeds.

Ah, I shall research these but they both sound like software to me. Hmm, unless "HELLO!" isn't software and you were just indicating that faster hardware is just so obvious.

Certainly faster hardware is coming at us; but a quadratic growth problem will *always* out scale even the greatest conceivable hardware.

A linear improvement in the software is always appreciated but again it is *only* linear (even if it is a massive 5x) as compared to quadratic growth, i.e. n². For example, suppose it takes t amount of time to process one sigop. Then a transaction with n sigops will take approximately n²*t amount time. Now we unleash the mighty libsecp256k1 5x improvement. So, we have n²*(t/5). When n is small this is great news. For example, 1²*t vs. 1²*(t/5) or 1t vs. t/5 gets us the full 5x advantage but 10²*t vs. 10²*(t/5) or 100t vs. 20t is still taking 20t and not 10t let alone 2t to do those 10 sigops. Moreover, 100 sigops works out to 10,000t vs. 2,000t; and who wants to compute 2,000t for just 100 sigops? Honestly/sincerely I am utterly delighted at the 5x offered by libsecp256k1 but against quadratic growth it pales.

1)how insane would a TX have to be to make it so validation time is hindered?
2)can we simply ignore TX that are that crazy?
3) is it conceivable that a legit TX would be that crazy?

i have no clue my guess is

1) extremely insane
2) yes
3) no

but guessing is not cool, would be nice if some math could back up me up.