Re: [bitcoin-dev] On Hardforks in the Context of SegWit

[Luke Dashjr <luke@dashjr.org>]

On Tuesday, February 09, 2016 10:00:44 PM Matt Corallo via bitcoin-dev wrote:
> Indeed, we could push for more place by just always having one 0-byte,
> but I'm not sure the added complexity helps anything? ASICs can never be
> designed which use more extra-nonce-space than what they can reasonably
> assume will always be available, so we might as well just set the
> maximum number of bytes and let ASIC designers know exactly what they
> have available. Currently blocks start with at least 8 0-bytes. We could
> just say minimum difficulty is now 6 0-bytes (2**16x harder) and reserve
> those?

The extranonce rolling doesn't necessarily need to happen in the ASIC itself. 
With the current extranonce-in-gentx, an old RasPi 1 can only handle creating 
work for up to 5 Gh/s with a 500k gentx.

Furthermore, there is a direct correlation between ASIC speeds and difficulty, 
so increasing the extranonce space dynamically makes a lot of sense.

I don't see any reason *not* to increase the minimum difficulty at the same 
time, though.

Luke