Den 1 apr. 2017 16:07 skrev "Jorge Timón" <jtimon@jtimon.cc>:
On Sat, Apr 1, 2017 at 3:15 PM, Natanael <natanael.l@gmail.com> wrote:
>
>
> Den 1 apr. 2017 14:33 skrev "Jorge Timón via bitcoin-dev"
> <bitcoin-dev@lists.linuxfoundation.org>:
>
> Segwit replaces the 1 mb size limit with a weight limit of 4 mb.
>
>
> That would make it a hardfork, not a softfork, if done exactly as you say.
>
> Segwit only separates out signature data. The 1 MB limit remains, but would
> now only cover the contents of the transaction scripts. With segwit that
> means we have two (2) size limits, not one. This is important to remember.
> Even with segwit + MAST for large complex scripts, there's still going to be
> a very low limit to the total number of possible transactions per block. And
> not all transactions will get the same space savings.

No, because of the way the weight is calculated, it is impossible to
create a block that old nodes would perceive as bigger than 1 mb
without also violating the weight limit.
After segwit activation, nodes supporting segwit don't need to
validate the 1 mb size limit anymore as long as they validate the
weight limit.

https://github.com/bitcoin/bips/blob/master/bip-0141.mediawiki#Block_size

Huh, that's odd. It really does still count raw blockchain data blocksize. 

It just uses a ratio between how many units each byte is worth for block data vs signature data, plus a cap to define the maximum. So the current max is 4 MB, with 1 MB of non-witness blockchain data being weighted to 4x = 4 MB. That just means you replaced the two limits with one limit and a ratio. 

A hardfork increasing the size would likely have the ratio modified too. With exactly the same effect as if it was two limits... 

Either way, there's still going to be non-segwit nodes for ages.