Set transaction fee in app.

[Michael Rochester]

The user should be able to specify the transaction fee.

Once the new transaction fee implementation appears, this will most likely just be a couple of options. The default option will be a cheap fee, with an alternative option for a higher fee when fast confirmation is required.

[Sam Bull (dreamsorcerer)]

When the new transaction fee implementation lands in the bitcoin protocol, bitcoin libraries should automatically use a fee that is high enough to get included into the block chain, but with a low cost. Thus, this is a low priority, and may even be irrelevant after that change.

It could be an idea to allow the user to choose if they want a high fee that ensures the transaction will get included in the next block, or a low fee if time is not essential, leaving the exact fee amounts for the software to decide.

We'll revisit it when the new fee design has been implemented.

[Marco (jermy-07)]

Thanks for the comment; do you have a link with further information about the "new fee design"?

Also: What is the current fee paid per transaction? .001 BTC?

[Michael Rochester (codeforger)]

The current fee for our app is 100 μBTC (0.0001 BTC), however this is per kilobyte as apposed to per transaction, this means if you send money to two recipients at one time the fee is unlikely to rise.

As most transactions are smaller than 1/4 kilobytes (http://blockchain.info/tx/6924b672f97658bd1af1b7255c6fa132cfd624110c5a0f252f45b1e210d727cf) you could get up to 4 transactions in one send without seeing a fee rise.

[Sam Bull (dreamsorcerer)]

I think the idea is mostly documented in this page: https://gist.github.com/gavinandresen/2961409

As Michael said, the transaction fee is currently 100 μBTC, which is the standard fee coded into the network. It's possible that a lower fee could be used without any negative effects though, so we'll look at lowering the default fee until the new transaction system is put into place.

[Marco (jermy-07)]

100 μBTC seem just fine as transaction fee right now for this mobile app which is supposed to do micro payments. However, the problem I see is that the fee is hard-coded and not dynamically calculated (c.f. second bullet point in the first section of the link Sam posted)

Imagine one bitcoin is worth 9800$ in 11 months and I want to buy a cup of coffee. I had to pay ~.00015 BTC for the coffee and another .0001 transaction fee which makes a total of .00025. (Effectively paying a transaction fee which is greater than 50% of the price I had to pay originally)

As long as the transaction fee is not dynamically calculated (depending on the current parameters of "the market") the user should at least have the option to set a fee which is OK for him. (Approving that his transaction will potentially not get confirmed in the next few blocks or not at all)

[Sam Bull (dreamsorcerer)]

Right, that's exactly the reason for the new implementation. The hardcoded fee of 100 μBTC was actually put in place like a year ago or something, so with the value having shot up like 10x what is was back then, the fee is actually considered quite expensive. And, if you think about just sending money to a friend, that's around $0.10 in fees. So, if it's safe to lower the fee, we'll do that as a temporary measure until the new implementation appears.

[Sam Bull (dreamsorcerer)]

OK, so I'm told it's not safe to change the transaction fee. So, it will need to remain as is, until the new implementation lands. See a discussion at: https://github.com/bitcoin/bitcoin/pull/3305

[Marco (jermy-07)]

As of now it is possible to do a transaction with a 0,01 mBTC fee. Though it may take 2-3 blocks to get a confirmation.

[Sam Bull (dreamsorcerer)]

Yep, the fee is set in bitcoinj though, and the current release of this library is still at 0.1 mBTC. We're preparing to change libraries soon, so we'll likely revisit this once after the switch.

[Marco (jermy-07)]

> we'll likely revisit this once after the switch.

Did the "switch" happen? I could look into this myself but I am not sure if this app is still developed.

[Michael Rochester (codeforger)]

Hi Marco.

We are currently very close to deploying the Python version (the so called
switch).

Once this is done, we will revisit and triage all the bugs once again.

With the python version development and releasing is far easier so there
will hopefully be a faster turn around on these issues.

Thanks,
    Michael

On Sat, 30 Jan 2016, 15:05 Marco <email address hidden> wrote:

> > we'll likely revisit this once after the switch.
>
> Did the "switch" happen? I could look into this myself but I am not sure
> if this app is still developed.
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1261507
>
> Title:
> Set transaction fee in app.
>
> Status in Bitcoin Touch:
> Triaged
>
> Bug description:
> The user should be able to specify the transaction fee.
>
> Once the new transaction fee implementation appears, this will most
> likely just be a couple of options. The default option will be a cheap
> fee, with an alternative option for a higher fee when fast
> confirmation is required.
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/bitcoin-app/+bug/1261507/+subscriptions
>