Bisq does not check mempoolminfee when creating new transactions

[wiz]

Following up from discussions on Keybase, Bisq needs to enforce mempoolminfee value, since it currently uses a hard-coded value and the network value is variable:

1. Pricenode needs to save the minimumFee value from https://mempool.space/api/v1/fees/recommended
2. Pricenode needs to serve the minimumFee value from (1) on https://price.bisq.wiz.biz/getFees
3. Bisq needs to save the minimumFee value it gets when updating from (2) once per minute
4. Bisq needs to return the minimumFee value it gets from (3) in bisq.common.config.BaseCurrencyNetwork::getDefaultMinFeePerVbyte()

cc @jmacxx

[wiz]

Also, we should multiply by the minimumFee by 2, so even if it goes down to 1 the actual minimum is still 2 as it was before with the hard-coded value, and when it's > 1 this gives some buffer to avoid immediate purging of the user's TX

[Emzy]

Alternative option, or quick fix, could be to increase the mempool on our nodes we use for TX transmissions.

[wiz]

No, it doesn't matter if our nodes accept or reject the low-fee transactions, no other nodes will accept them

[Emzy]

Sure. It was about the problem of the resync of the wallet part. But if I think more about it, the increase will make the problem even bigger. So not a good idea.

[wiz]

Yes, this is why typically only miners and block explorers change their mempool settings - normal users changing it does not have any benefit and only negative effects