There is incentive because of artificially distorted block weight rules. It
is favourable for a miner to choose a segwit tx over a non segwit tx as
they can fit more of them into a block and earn more fees.

On Nov 21, 2017 11:06 PM, "Dan Bryant via bitcoin-dev" <
bitcoin-dev@lists.linuxfoundation.org> wrote:

> Is there any incentive for miners to pick segwit transactions over
> non-segwit transaction.  Do they require less, equal, or more compute to
> process?
>
> On Nov 20, 2017 11:46 AM, "Johnson Lau via bitcoin-dev" <
> bitcoin-dev@lists.linuxfoundation.org> wrote:
>
> We can’t “just compute the Transaction ID the same way the hash for
> signing the transaction is computed” because with different SIGHASH flags,
> there are 6 (actually 256) ways to hash a transaction.
>
> Also, changing the definition of TxID is a hardfork change, i.e. everyone
> are required to upgrade or a chain split will happen.
>
> It is possible to use “normalised TxID” (BIP140) to fix malleability
> issue. As a softfork, BIP140 doesn’t change the definition of TxID.
> Instead, the normalised txid (i.e. txid with scriptSig removed) is used
> when making signature. Comparing with segwit (BIP141), BIP140 does not have
> the side-effect of block size increase, and doesn’t provide any incentive
> to control the size of UTXO set. Also, BIP140 makes the UTXO set
> permanently bigger, as the database needs to store both txid and normalised
> txid
>
> On 21 Nov 2017, at 1:24 AM, Praveen Baratam via bitcoin-dev <
> bitcoin-dev@lists.linuxfoundation.org> wrote:
>
> Bitcoin Noob here. Please forgive my ignorance.
>
> From what I understand, in SegWit, the transaction needs to be serialized
> into a data structure that is different from the current one where
> signatures are separated from the rest of the transaction data.
>
> Why change the format at all? Why cant we just compute the Transaction ID
> the same way the hash for signing the transaction is computed?
>
> --
> Dr. Praveen Baratam
>
> about.me <http://about.me/praveen.baratam>
> _______________________________________________
>
> bitcoin-dev mailing list
> bitcoin-dev@lists.linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>
>
>
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev@lists.linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>
>
>
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev@lists.linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>
>