[bitcoin-discuss] Bitcoin dev IRC meeting in layman's terms (2015-11-26)

Mon Nov 30 17:11:02 UTC 2015

Once again my attempt to summarize and explain the weekly bitcoin developer
meeting in layman's terms.
Link to last weeks summarization (
http://lists.linuxfoundation.org/pipermail/bitcoin-discuss/2015-November/000028.html
)

*Disclaimer*

Please 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.

link to this week logs (
http://bitcoinstats.com/irc/bitcoin-dev/logs/2015/11/26#l1448565880.0 )
Meeting minutes by meetbot (
http://www.erisian.com.au/meetbot/bitcoin-dev/2015/bitcoin-dev.2015-11-26-19.24.html
)

Main topics discussed where:

CLTV activation
BIP68/BIP112 implementation
Replace-by-fee

**Short topics/notes**

It was an American holiday (thanksgiving), so there weren't a lot of people
in the meeting, which started later as well.

Personal note: My weekly posts are being read by more people than I ever
anticipated and people are expecting these to come weekly.
Next year Mid-February I'll be on vacation for a month, so that's 4 or 5
meetings I won't be able to do.
If there's anyone who's up for the challenge to take over during those
weeks (or maybe just 1 week and share the load with others) feel free to pm
me.
I'm announcing well in advance, so there's more chance to find someone and
to not make this a last minute thing.
I'd prefer someone who doesn't work in the bitcoin space (coding), as I
much rather have people work on the future of money instead of enlightening
us noobs :)

**CLTV activation**

- background

CheckLockTimeVerify (CLTV) aka "how you thought nLockTime worked before you
actually tried to use it" aka OP_HODL.

- meeting comments

It's plausible the CLTV softfork will activate within just a few weeks, as
everyone but a few big miners have adopted it.
About 20% of the nodes currently run CLTV-supporting versions. The negative
effect of not upgrading is a degraded validation (SPV).

- meeting conclusion

Do a social media reminder to upgrade nodes to v0.11.2/v0.10.4

**BIP68/BIP112 implementation**

- background

BIP 68 ( https://github.com/bitcoin/bips/blob/master/bip-0068.mediawiki )
 Consensus-enforced transaction replacement signaled via sequence numbers ,
and current implementation ( https://github.com/bitcoin/bitcoin/pull/6312
).
BIP 112 ( https://github.com/bitcoin/bips/blob/master/bip-0112.mediawiki )
CHECKSEQUENCEVERIFY, and current implementation (
https://github.com/bitcoin/bitcoin/pull/6564 ).
In short: BIP 68 changes the meaning of the sequence number field to a
relative locktime. BIP 112 makes that field accessible to the bitcoin
scripting system.

- meeting comments

The BIP68 and BIP112 texts have been updated to match the implementations.
There's been a call and discussion to rename CHECKSEQUENCEVERIFY on the
mailinglist (
https://www.mail-archive.com/bitcoin-dev@lists.linuxfoundation.org/msg02876.html
).
btcdrak wants both pull-requests to be merged soon, others feel more
hesitant as people seem to only recently started looking at it seriously.

- meeting conclusion

Merge updated BIP-texts

**Replace-by-fee**

- background

Currently when a node sees a transaction that spends the same output it
ignores it. With replace-by-fee it replaces the current transaction in the
mempool if it has a higher fee.
This allows for things like spending "stuck" transactions, adding more
recipients to a transaction in order to prevent chaining, etc.

Since there are people that accept 0-confirmation transactions and this
would make it extremely easy to double spend them, this is made opt-in.
The sender can choose to opt-in to replace-by-fee by changing the nSequence
field of all inputs.
This is a mempool policy for the upcoming 0.12 release.
There's a good FAQ-ish post (
https://www.reddit.com/r/Bitcoin/comments/3urm8o/optin_rbf_is_misunderstood_ask_questions_about_it/
) on reddit about it.

- meeting comments

petertodd ran some tests with the mempool limiter turned way down and saw
no issues.
It should be technically easy to merge first-seen-safe and
full-unconditional as options if there's people who want to write it.

- meeting conclusion

test and ACK replace-by-fee ( https://github.com/bitcoin/bitcoin/pull/6871
) (Has been merged meanwhile).

**Participants**

    btcdrak      btcdrak
    petertodd    Peter Todd
    Luke-Jr      Luke Dashjr
    CodeShark    Eric Lombrozo
    sipa            Pieter Wuille
    jtimon       Jorge Timón

**Comic relief**

    19:17 btcdrak wumpus: so no meeting today then?
    19:17 CodeShark btcdrak: so no wumpus today then? :)
    19:17 petertodd btcdrak: since when do you listen to authority? :P

    19:22 CodeShark is there a quorum? or can we meet anyhow? :)
    19:22 petertodd      CodeShark: I'm in a mcdonalds right now, working
on increasing my influence, as measured by mass...
    19:22 petertodd     CodeShark: so yes

    19:49 btcdrak ### 10 minutes left. are there any other topic
suggestions?
    19:50 petertodd    btcdrak: rbf
    19:50 btcdrak #topic RBF
    19:51 CodeShark anyone have a topic that pays a higher fee? :)
    19:51 Luke-Jr this fee is too low, I'm leaving early!

    19:24 btcdrak #meetingstart
    19:24 btcdrak #startmeeting
    19:24 lightningbot Meeting started Thu Nov 26 19:24:40 2015 UTC. The
chair is btcdrak. Information about MeetBot at
http://wiki.debian.org/MeetBot.

    20:00 btcdrak #endmeeting
    20:00 btcdrak #meetingend
    20:00 btcdrak oh ffs, not this problem again
    20:00 lightningbot Meeting ended Thu Nov 26 20:00:24 2015 UTC.
Information about MeetBot at http://wiki.debian.org/MeetBot . (v 0.1.4)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.linuxfoundation.org/pipermail/bitcoin-discuss/attachments/20151130/505be92a/attachment.html>