Subject: Re: [bitcoin-dev] Fees and the block-finding process

From: Pieter Wuille <[email-masked]>
Date: Fri, 7 Aug 2015 17:16:34 +0200

On Fri, Aug 7, 2015 at 4:57 PM, Gavin Andresen via bitcoin-dev <
[email-masked]> wrote:

> Every once in a while the network will get lucky and we'll find six blocks
> in ten minutes. If you are deciding what transaction fee to put on your
> transaction, and you're willing to wait until that
> six-blocks-in-ten-minutes once-a-week event, submit your transaction with a
> low fee.
>
> All the higher-fee transactions waiting to be confirmed will get confirmed
> in the first five blocks and, if miners don't have any floor on the fee
> they'll accept (they will, but lets pretend they won't) then your
> very-low-fee transaction will get confirmed.
>
> In the limit, that logic becomes "wait an infinite amount of time, pay
> zero fee."
>

That's only the case when the actual rate of transactions with a non-zero
fee is below what fits in blocks. If the total production rate is higher,
even without configured floor by miners, a free transaction won't ever be
mined, as there will always be some backlog of non-free transaction. Not
saying that this is a likely outcome - it would inevitably mean that people
are creating transactions without any guarantee that they'll be mined,
which may not be what anyone is interested in. But perhaps there is some
"use" for ultra-low-priority unreliable transactions (... despite DoS
attacks).

>
> So... I have no idea what the 'market minimum fee' will be, because I have
> no idea how long people will be willing to wait, how many times they'll be
> willing to retransmit a low-fee transaction that gets evicted from
> memory-limited memory pools, or how much memory miners will be willing to
> dedicate to storing transactions that won't confirm for a long time because
> they're waiting for a flurry of blocks to be found.
>

Fair enough, I don't think anyone knows.

I guess my question (and perhaps that's what Jorge is after): do you feel
that blocks should be increased in response to (or for fear of) such a
scenario. And if so, if that is a reason for increase now, won't it be a
reason for an increase later as well? It is my impression that your answer
is yes, that this is why you want to increase the block size quickly and
significantly, but correct me if I'm wrong.

-- 
Pieter