Meetings: add 2018-05-17

- High priority for review
- 0.16.1 prep for RC1
- Trashing GitHub
- Separate wallet from node
- Unverified-block-message

Author: harding

_includes/_references.md

@@ -48,6 +48,7 @@
 [Saleem Rashid]: https://github.com/saleemrashid
 [Samuel Dobson]: https://github.com/MeshCollider
 [Sjors Provoost]: https://github.com/sjors
+[Steve Lee]: https://github.com/moneyball
 [Suhas Daftuar]: https://github.com/sdaftuar
 [Tadge Dryja]: https://github.com/T909
 [Tom Harding]: https://github.com/dgenr8

_posts/en/meetings/2018-05-17-meeting.md

@@ -0,0 +1,267 @@
+---
+title: IRC meeting summary for 2018-05-17
+permalink: /en/meetings/2018/05/17/
+name: 2018-05-17-meeting
+type: meetings
+layout: page
+lang: en
+version: 1
+---
+{% include _toc.html %}
+{% include _references.md %}
+
+- View this week's log on [BotBot.me](https://botbot.me/freenode/bitcoin-core-dev/msg/100174747/) or [MeetBot](http://www.erisian.com.au/meetbot/bitcoin-core-dev/2018/bitcoin-core-dev.2018-05-17-19.00.log.html)
+- [Meeting minutes by MeetBot](http://www.erisian.com.au/meetbot/bitcoin-core-dev/2018/bitcoin-core-dev.2018-05-17-19.00.html)
+
+---
+
+Topics discussed during this weekly meeting included what pull requests
+the meeting participants most want to see reviewed, what issues need to
+be resolved before generating the first release candidate for version
+0.16.1, whether or not the project should leave GitHub, a request for
+review for a PR that paves the path towards separating node code from
+wallet code, and a potential new P2P protocol message to better handle
+relay of unverified blocks.
+
+## High priority for review
+
+**Background:** each meeting, Bitcoin Core developers discuss which Pull
+Requests (PRs) the meeting participants think most need review in the
+upcoming week.  Some of these PRs are related to code that contributors
+especially want to see in the next release; others are PRs that are
+blocking further work or which require significant maintenance (rebasing)
+to keep in a pending state.  Any capable reviewers are encouraged to
+visit the project's list of [current high-priority PRs][].
+
+**Discussion ([log](http://www.erisian.com.au/meetbot/bitcoin-core-dev/2018/bitcoin-core-dev.2018-05-17-19.00.log.html#l-13)):**
+PRs specifically discussed included,
+
+- **[#12254][]:** BIP 158: Compact Block Filters for Light Clients
+
+- **[#12196][]:** Add scantxoutset RPC method
+
+- **[#13142][]:** Separate IsMine from solvability
+
+- **[#12979][]:** Make reusable base class for auxiliary indices
+
+In addition, Wladimir van der Laan expressed concerns that the list was
+getting quite long.
+
+## 0.16.1
+
+**Background:** Bitcoin Core developers have begun preparing a new
+0.16.1 [maintenance release](/en/lifecycle/#maintenance-releases) with
+bugfixes and backports of important features.
+
+**Discussion
+([log](http://www.erisian.com.au/meetbot/bitcoin-core-dev/2018/bitcoin-core-dev.2018-05-17-19.00.log.html#l-65)):**
+Wladimir van der Laan proposed the topic and provided a brief survey of
+the work that still needs to be done:
+
+1. **[0.16] Further Backports ([#13253][]).**   Needs more review.
+
+2. **0.16.0 bitcoin-qt: "Assertion `copyFrom failed" during launch
+   ([#13110][]).**  Van der Laan says he "proposed a fix for [this] and
+   it apparently worked."
+
+3. **Assertion failure during rescan ([#12646][]).**  Jonas Schnelli
+   suggested bumping, and Van der Laan agreed.  It was retargeted to
+   0.16.2.
+
+4. **0.16 Shutdown assertion ([#12337][]).**  Schnelli is investigating
+   this.
+
+**Conclusion:** "We just need to finish backports and tag for
+0.16.1RC1," said Matt Corallo.
+
+## Trashing GitHub
+
+**Background:** for more than 6 weeks now, the webpages for
+highly-reviewed Bitcoin Core PRs on GitHub have frequently failed to
+load, with reviewers seeing an illustration of an angry unicorn instead.
+The issue has been reported several times to GitHub support by different
+people but has not yet been resolved.
+
+**Discussion
+([log](http://www.erisian.com.au/meetbot/bitcoin-core-dev/2018/bitcoin-core-dev.2018-05-17-19.00.log.html#l-97)):**
+Matt Corallo requested the topic and introduced it:  "It hasn't been
+working [...] and I'd kinda like to have something self-hosted with
+better review tools anyway, which I know a lot of people wanted."
+
+Pieter Wuille and Wladimir van der Laan suggested that GitLab was an
+alternative, which Corallo accepted but noted, "though GitLab seems to
+have no better review tools than GitHub."
+
+Suhas Daftuar was concerned that, "it seems to me like it's way harder
+to get it right hosting ourselves."  Van der Laan had the same concern,
+"Who is going to babysit this, monitor it, and apply security patches,
+etc...?"
+
+Cory Fields added, "General NACK: self-hosting issues aside, GitHub's
+network effect is too strong [in my opinion].  I can't be the only one
+who gets irrationally frustrated when the code I want to mess with is on
+BitBucket."  Van der Laan agreed, "Yes, only [large] players like
+FreeDesktop can really afford to host on separate infrastructure; for
+smaller projects the lack of network effect (and having to register
+separately) is bad."  John Newbery also agreed.
+
+Talking about features he'd like to see in a GitHub replacement, Corallo
+wished there was a command-line way to "verify, e.g., PGP signatures on
+comments."  That way if anyone compromised the repository web service to
+forge an ACK on a PR, it could be detected before merge.
+
+Jim Posen and Steve Lee offered to help get more information about
+the issue from GitHub.  The Bitcoin Core project is not the only one
+suffering from the issue, with Corallo saying "Some other projects were
+posting responses they got where [GitHub support was] saying, 'we don't
+actually know what change we made that triggered these issues, hold
+on.'  But that was three weeks ago."
+
+**Conclusion:** Corallo decided there was too much adversity to the idea
+at the moment, so "I'm not gonna spend time looking into it."  Van der
+Laan concluded, "I don't think there's realistically any chance of
+anything replacing GitHub until someone sets up a feasible alternative
+and shows us that it is better."
+
+**Post-meeting:** about a day after the meeting, Jonas Schnelli received
+a
+[message](https://0bin.net/paste/ViHtKCgPIfW0TMYt#j30mFske0y1EVoVRZCsQqMoYCpoPc3axAV29jkKkznB)
+from Ben Balter, a product manager at GitHub, saying that GitHub has
+"identified the root cause, and are working on a fix."
+
+## Separate wallet from node
+
+**Background:** Bitcoin Core's full node implementation, wallet, and
+Graphical User Interface (GUI) all currently run as a single process
+(although the wallet and the GUI can be disabled).  This means, for
+example, that if you close the GUI, you also stop the node.  It has been
+a long-term goal of several contributors to split these different parts
+into separate processes so that they can be operated independently of
+one another.
+
+**Discussion
+([log](http://www.erisian.com.au/meetbot/bitcoin-core-dev/2018/bitcoin-core-dev.2018-05-17-19.00.log.html#l-234)):**
+John Newbery requested the topic and introduced it:  "[#10973][] is a
+big PR, but I think it's very worthwhile, [...] but it requires
+continual rebase.  [...] I think it'd be great to make some progress on
+this one."
+
+Wladimir van der Laan was concerned that the high-priority review queue
+is too large: "Oh, no, not more high priority for review.  Is it
+blocking anything?  Is it important for 0.17?  Process separation is not
+something we'll have for 0.17 anyway."
+
+The author of the PR, Russell Yanofsky, offered to split the first six
+commits off to a separate PR so that they can be reviewed independently
+of the later commits, reducing the size of the PR and hopefully making
+it easier to review.
+
+**Conclusion:** With Yanofsky offering to split the PR and a few
+contributors offering to review it in the upcoming week, Newbery closed
+the topic.
+
+## Unverified-block-message
+
+**Background:** [BIP152][] compact block relay introduced a
+high-bandwidth mode where a node can send information to its peers about
+a new block before the node has finished validating that block.  If the
+node does finish validating the block and finds that the block is invalid,
+but the peers request the whole block anyway, there's currently no way
+for the node to tell its peers that it doesn't have a valid block to send
+them.  Currently, in this case, the peers will eventually disconnect
+from the node for failing to send the requested block.
+
+**Discussion
+([log](http://www.erisian.com.au/meetbot/bitcoin-core-dev/2018/bitcoin-core-dev.2018-05-17-19.00.log.html#l-268)):**
+Matt Corallo requested the topic and introduced it by describing two
+potential solutions to the problem:
+
+1. The node tells requesting peers that it refuses to relay the block.
+
+2. The node gives the peers the requested block, proving it has valid
+   block headers (as required by BIP152), but also tags it as
+   potentially invalid.
+
+Pieter Wuille suggested that the existing [`notfound`][p2p notfound]
+message could possibly be reused as part of implementing the first
+proposed solution.
+
+Suhas Daftuar argued against reusing the `notfound` message in favor of
+the second proposed solution: "I think notfounds are worse because of
+the case where the block might not have been validated either way."
+Wladimir van der Laan agreed that a new message should be used "if
+there's no specific reason to re-use `notfound`, a new message is much
+better."
+
+**Conclusion:** Corallo was still considering the options, but thought
+it was "good to ask.  Obviously [the actual solution] requires a BIP and
+whatever else."
+
+## Other topics
+
+With just minutes remaining in the meeting, Matt Corallo proposed
+a topic titled "Queue drain lock assertions to avoid deadlocks," but
+there wasn't enough time to discuss the topic and Corallo said, "I
+realize now I should just open a PR and people will see it, [as] it's
+kinda knotty to describe."
+
+## Comic relief
+
+{% highlight text %}
+<BlueMatt> trashing github
+<BlueMatt> or we could switch to gitlab
+    <sipa> let's move back to sourceforge
+{% endhighlight %}
+
+{% highlight text %}
+<sdaftuar> i think we could just add a new BLOKC response type
+           BLOCK_COULDBEBAD
+    <sipa> 0xDEADB10C
+  <wumpus> hehe
+{% endhighlight %}
+
+
+## Participants
+
+| IRC nick        | Name/Nym                  |
+|-----------------|---------------------------|
+| BlueMatt        | [Matt Corallo][]          |
+| wumpus          | [Wladimir van der Laan][] |
+| sipa            | [Pieter Wuille][]         |
+| jonasschnelli   | [Jonas Schnelli][]        |
+| jnewbery        | [John Newbery][]          |
+| jtimon          | [Jorge Timón][]           |
+| jimpo           | [Jim Posen][]             |
+| sdaftuar        | [Suhas Daftuar][]         |
+| cfields         | [Cory Fields][]           |
+| MarcoFalke      | [Marco Falke][]           |
+| jamesob         | [James O'Beirne][]        |
+| promag          | [Joao Barbosa][]          |
+| moneyball       | [Steve Lee][]             |
+| ryanofsky       | [Russell Yanofsky][]      |
+| kanzure         | [Bryan Bishop][]          |
+
+## Disclaimer
+
+This summary was compiled without input from any of the participants in
+the discussion, so any errors are the fault of the summary author and
+not the discussion participants.  In particular, quotes taken from the
+discussion had their capitalization, punctuation, and spelling modified
+to produce consistent sentences.  Bracketed words and fragments, as well
+as background narratives and exposition, were added by the author of
+this summary and may have accidentally changed the meaning of some
+sentences.  If you believe any quote was taken out of context, please
+[open an issue](https://github.com/bitcoin-core/bitcoincore.org/issues/new)
+and we will correct the mistake.
+
+[#10973]: https://github.com/bitcoin/bitcoin/issues/10973
+[#12196]: https://github.com/bitcoin/bitcoin/issues/12196
+[#12254]: https://github.com/bitcoin/bitcoin/issues/12254
+[#12337]: https://github.com/bitcoin/bitcoin/issues/12337
+[#12646]: https://github.com/bitcoin/bitcoin/issues/12646
+[#12979]: https://github.com/bitcoin/bitcoin/issues/12979
+[#13110]: https://github.com/bitcoin/bitcoin/issues/13110
+[#13142]: https://github.com/bitcoin/bitcoin/issues/13142
+[#13253]: https://github.com/bitcoin/bitcoin/issues/13253
+[p2p notfound]: https://bitcoin.org/en/developer-reference#notfound
+[current high-priority PRs]: https://github.com/bitcoin/bitcoin/projects/8