Subject: Re: [bitcoin-dev] Why not Child-Pays-For-Parent?

From: Tier Nolan <[email-masked]>
Date: Sun, 12 Jul 2015 00:19:14 +0100

On Sat, Jul 11, 2015 at 10:30 PM, Dan Bryant <[email-masked]> wrote:

> I think a compromise will be somewhere in the middle.  I think most people
> would be OK with TXs that don't have enough fees for P2P transfer to stay
> in deadmans land.  Most people are stuck in a situation where they payed
> enough to get it into (and keep it in) the pool, but not enough to get it
> out.
>

Agreed.  A lot of the functionality could be achieved by a system that
works in most cases.  Even if 100 transaction chains aren't supported, 3-5
transaction chains would give a significant fraction of the desired
functionality.

At the moment, a transaction is only added into the memory pool if it meets
the relay threshold and spends transactions that are either in the memory
pool or in a block.

There is an orphan pool that can store up to 100 orphans.

The same could be done for child pays for parent.  A node could remember
the last 100 transactions (up to 5000 bytes) that were rejected from the
memory pool due to insufficient relay fees.

This allows nodes to send a chain of transactions in a row.  If the child
is sent last, then the parent(s) will be in the unrelayed transaction pool.