Once again my attempt to summarize and explain the weekly bitcoin developer meeting in layman's terms.
Link to last weeks summarization DisclaimerPlease bear in mind I'm not a developer and I'd have problems coding "hello world!", so some things might be incorrect or plain wrong.
Like any other write-up it likely contains personal biases, although I try to stay as neutral as I can.
There are no decisions being made in these meetings, so if I say "everyone agrees" this means everyone present in the meeting, that's not consensus, but since a fair amount of devs are present it's a good representation.
The dev IRC and mailinglist are for bitcoin development purposes. If you have not contributed actual code to a bitcoin-implementation, this is probably not the place you want to reach out to. There are many places to discuss things that the developers read, including this forum.
link to this week logs Meeting minutes by meetbot Main topics discussed where:
transaction priority
dealing with mempool eviction
Sequence numbers
Short topics/notes Opt-in replace by fee needs some extra testing, but otherwise seems ready to go. Some wallet developers are on board and actively participating, for example GreenAddress.
transaction priority- background Each transaction is assigned a priority, determined by the age, size, and number of inputs. Which currently makes some transactions free.
This currently has a large amount of code, which makes it harder to maintain, and is not that optimal since you can't expect miners to include 0-fee transactions.
- meeting commentsIf we don't stop support for priority in transaction creation we also need a mempool area for priority, or those transactions will always get evicted.
If we develop a better framework to support these kind of metrics we can add it back.
Plan is to remove the priority transaction creation from the wallet, not the mining part.
- meeting conclusion Creation of priority transactions should be removed from the wallet.
dealing with mempool eviction- background When a transaction is relayed across the network it is held by the nodes in memory, until it gets into a block. All these transactions that sit in memory are called the memorypool or mempool for short.
Like we could see during the spam-attack if there's a big back-log of transactions that couldn't make it in the blockchain this mempool can get pretty big resulting in nodes crashing.
To stop this from happening devs created a mechanism to reject and/or remove transactions from the mempool.
- meeting commentsCurrent problem: when a wallet transaction is rejected by the mempool, the wallet considers the resulting transaction as "conflicting" and will happily respend the inputs.
sipa proposes to make the wallet only treat a transaction as conflicting if it has non-existing inputs.
It should however consider it respendable at some time later on.
You could add a way to manually remove transactions, or tag is as removed, or archive it.
You could also do something separate that marks the transaction as respendable, as removal gives the impression the transaction can't be mined in the future.
Options that are wanted: a "respend with higher fee" option and an option to forget about a transaction completely, we need a minimum viable idea for 0.12 though.
- meeting conclusionGiven the tight deadline for 0.12 we detect actual conflict instead of mempool eviction and leave the coins immediately respendable.
Sequence numbers- backgroundBIP 68 repurposes some of the unused nSequence field to a relative locktime, meaning locking inputs until a certain time or blockheight has passed.
- meeting commentsWe need to wait for BIP113 to be deployed as standardness so
BIP 68,
112 and
113 can go in a softfork.
There's upcoming projects that already use sequence numbers.
Merging BIP68 would make BIP112 easier to review and would stop the need to
rebase all the time.
If we feel the 68/112 are sufficiently reviewed and mature they could go in as standardness rules.
The BIP text doesn't seem to reflect what's written in the code.
- meeting conclusionCheck BIP68 to match the
implementationParticipants sipa Pieter Wuille
gmaxwell Gregory Maxwell
morcos Alex Morcos
jtimon Jorge Timón
wumpus Wladimir J. van der Laan
btcdrak btcdrak
jgarzik Jeff Garzik
petertodd Peter Todd
Luke-Jr Luke Dashjr
BlueMatt Matt Corallo
jonasschnelli Jonas Schnelli
CodeShark Eric Lombrozo
sdaftuar Suhas Daftuar
gavinand1esen Gavin Andresen
