fundchannel with feerate=urgent leads to transaction getting stuck in mempool

[lightningorb]

fundchannel with a feerate set to 'urgent' leads to 5 sat/vb which, given the current state of the mempool leads to the transaction getting stuck in the mempool.

It seems these:

• slow
• normal
• urgent

feerate values are not being calculated properly given the current state of the mempool. The documentation states that urgent (aim for next block) which is not the case.

[lightningorb]

Also the documentation for setting the feerate manually is not clear:

Otherwise, feerate is a number, with an optional suffix: perkw means the number is interpreted as satoshi-per-kilosipa (weight), and perkb means it is interpreted bitcoind-style as satoshi-per-kilobyte. Omitting the suffix is equivalent to perkb.

It's not straightforward translating sat per vb from mempool.space into fundchannel feerate values. Could you please provide some examples.

[lightningorb]

Example this is a batch open performed with feerate=urgent

[lightningorb]

https://mempool.space/tx/3395923947ba732261aae82d275f806357bbbbdab8d83c56f34a6959b0938e60

[rustyrussell]

fundchannel with a feerate set to 'urgent' leads to 5 sat/vb which, given the current state of the mempool leads to the transaction getting stuck in the mempool.

It seems these:

* `slow`

* `normal`

* `urgent`

feerate values are not being calculated properly given the current state of the mempool. The documentation states that urgent (aim for next block) which is not the case.

Indeed, it's actually using the 6 block estimate for "urgent". This was an accidental side-effect of lowering fee estimates for v0.10.1! 😬

The next release allows "2blocks" so you can control this more sanely, and I will fix the documentation for "urgent" to be correct. I'll also add docs about pervB -> perkb!