Child Pay For Parent tx (CPFP) to get rid of unconfirmed transactions

We still get issues with stuck transactions if one of the traders used old unconfirmed txs as inputs for trades.
With the new version 0.4.9.9.3 we use a higher tx fee which should be sufficient to get confirmed fast but if there are inputs from old txs which are still not confirmed we still get stuck trades ;-(.

To avoid those follow up problems please check under the “Funds/Transactions” screen if you have unconfirmed transactions. If so check on the block explorer the fee. It has to be about 300-400 Sat/Byte to be sufficiently high (u can check here https://bitcoinfees.21.co) to get included to the blockchain.

If there are txs with lower fees you can get them confirmed by a “Child Pay For Parent” tx (CPFP).
It is just a tx where you use unconfirmed txs as inputs and bump up the tx fee so that the total fee of all txs is sufficiently high for a miner to include it. You just send to yourself your own BTC from unconfirmed txs (you get a new receiving address under “Funds/Deposit funds”).

To calculate the required fee you have to sum up all the sizes of the txs and the attached fees and see what is missing for the target fee (min. 300 sat/byte, better 400).
ps: 1000 sat = 0.00001000 BTC
Example:
Unconfirmed tx 1: size 300 byte, fee 50 000 sat -> 166 sat/byte
Unconfirmed tx 2: size 800 byte, fee 100 000 sat -> 125 sat/byte

Fee to add to get old txs confirmed:
Total size: 300 byte + 800 byte = 1100 byte
Fee already attached: 50 000 + 100 000 = 150 000 sat
Required fee for 400 sat/byte: 440 000 sat
Missing fee: 440 000 - 150 000 = 290 000 sat

So if the CPFP tx has 400 bytes you need to use a fee of 290 000 + 160 000 = 450 000 sat to get an overall average fee of 400 sat/byte.

You can set the withdrawal fee at the Settings and you will see the calculated tx fee when you do the withdrawal in a popup before it gets published. There you will see the real fee used and you can adjust the withdrawal fee in the Settings if it is not matching the fee you want to attach.
You can see in the popup also the real size of the CPFP tx and adjust the required fee if needed.
So it might take a bit of trying out a few different values in the Settings until you get close to the desired fee.

In the next release (v0.5) we will use dynamic fees and a fee estimation service so such issues will get solved, but for now that is the best way to deal with stuck transactions.

4 Likes

Hi, Manfred.
Is this common, i.e. will most users have to deal with this kind of thing at some point?

It is not up to a chance, if that is your concern. You will not experience this if you use updated version of BItsquare and sufficient fees in your transactions form external wallets or older trades from an old version of Bitsquare.

No, it was just with the last version and the rapid increase of tx fee.

So I send btc to my bitsquare wallet I was sending btc from at the first place with high fee and it will confirm the withdrawal from that wallet, right?

I don’t think you got it right. In your case, as I understand, you need to make a transaction to your new bitcoin address from the bitcoin address you to which you have tried to withdraw your coins.

So you made a transaction with low fee from bitsquare to a bitcoin address A. Now you need to make a new bitcoin address B in your external wallet of choice and send those bitcoins from A to B, even tho it is not confirmed, but keep in mind that you need to not only set a higher fee, but a lot higher fee so that miners have a motivation to include both transactions. You can calculate this as specified above.

I used the transaction accelerator, but thanks for the reply :slight_smile:

My withdrawal transaction doesn’t even appear in the block explorer. My bitcoin balance is missing from my bisq, it was not sent. How do I recover my balance?


0.14181673 bitcoins

Try using cmd+e to withdraw your funds.

You can also try deleting SPV chain file in Settings.