Block non-convergence soon? | Bitcointalksearch.org

jgarzik

legendary

Activity: 1596

Merit: 1100

Quote from: mimarob on December 26, 2010, 06:10:08 AM

aha, so in general any given block with the nonce as the only variable is not likely to have a solution at all?

It is always possible that there is no solution for the entire range of nonce (0 - 0xffffffff).

However, the timestamp and extranonce are changed every few seconds, as is merkle tree root. This helps avoid a situation where we get stuck with no solutions.

Mike Hearn

legendary

Activity: 1526

Merit: 1134

There is an "extraNonce" part of the block. It's where the script would be in the generation transaction, called the coinbase data. When nonce overflows extraNonce is incremented.

mimarob

full member

Activity: 354

Merit: 103

aha, so in general any given block with the nonce as the only variable is not likely to have a solution at all?

Are there some statistics on how often the non-nonce parts of the current block changes?

davout

legendary

Activity: 1372

Merit: 1008

1davout

The nonce overflows very often, but the timestamp changes often too

, and even if it didn't the merkle root can

mimarob

full member

Activity: 354

Merit: 103

hello!

am I rightly informed that the nonce is only 32 bits?

Does this in turn mean that there are "only" 2^32 or about 4 billion (4E9) combinations to try for each block?

If so, then when network hashing capacity reaches 4 000 000 kHash/sec the block would be solved in one second on average?

This contradicts the onlïne hash-rate calculator, which states about 4 hours, at present difficulty.

Sorry if this has been up before, but I'm really puzzled..

Topic: Block non-convergence soon? (Read 1440 times)