@Jameson Lopp recently posted on X about the danger of "store and forget" for Bitcoin over decades. Unfortunately he's right.
Originally I stored my raw private keys and UTXOs (on paper, care taken) figuring that was standard. Then bitcoin core stopped supporting them! Other wallets tend only to support them for sweeping, and I wonder how long.
If I were storing funds today I would use BIP39. BIP93 is cool and more general, but not widely supported, and I don't know what support will look like in a decade.
Christian Decker made a side comment on my PR about a potential further optimization for Postgres. I spent an hour on it, trying to get it to fit in our db API.
Since my wife was out with friends last night, so I dived into the implementation in earnest after the kids in bed.
Man, this is a horrible API which forces you to understand the design and history of PostgreSQL.
Until v14, the async API only supports one request at a time. (Surprise!!) You must explicitly turn on pipelining. Then you get one or more responses per request, with NULL between them. This is because you can have multiple SQL statements per string, or other modes which split responses like this (?).
You can no longer use non-pipelining APIs, once you turn this on.
You can't use PQsendQuery in pipeline mode. You need to use the lower level PQsendQueryParams with NULL params. This is documented as literally "You can't use this in pipeline mode" without explanation (the docs otherwise imply it's just a convenient wrapper). This is why you should always check your error returns!
And your code will still block forever. You need to explicitly flush the pipeline, otherwise it's cached locally. There are multiple different APIs to do this, and I'm not sure which to use yet.
Also, if you get an error in a SQL query, you need to drain the pipeline, turn pipeline mode off and on again.
Finally, the documentation warns that you are in danger of deadlock unless you turn on non-blocking mode. This makes some sense: the server won't read more commands if you're not reading, but I would prefer it to buffer somewhere.
This whole API seems to be implemented by and for people who have deep familiarity with PostgreSQL internals.
Hope the latency gain for CLN is worth it!
I think I got nerd sniped into implementing online compaction for CLN's gossip store. Mainly from people agitating that we should use a DB for gossip messages.
This will speed startup and reduce memory usage. And it's only going to take me a couple of days' work, depending on how many side-cleanups I do.
It can be hard to tell a flawed implementation of a good idea from a bad idea. But trust me, this is gonna be great!
The last CLN release was terrible for really large nodes: the bookkeeper migrations were exponentially slow on Postgres, then the first call to bookkeeper would grind the node and even OOM it.
Some quickbfixes went in, and there will probably be another point release with those. Thanks to those who donated their giant accounting dbs!
But the exciting thing is all the optimization and cleanup work that came from me profiling how we handle this large data. Not just reducing the time (those single linked lists being abused!) which I've been spending the last weeks on, but last night I started measuring *latency* while we're under stress.
1. Anyone can spray us with requests: the initial problem was caused by bookkeeper querying a few hundred thousand invoices.
2. A plugin can spew almost infinite logs.
2. xpay intercepts every command in case xpay-handle-pay is set, so it can intercept "pay" commands.
Fixes:
1. Yield after 100 JSON commands in a row: we had logic for autoclean, but that was 250ms, not count based. We now do both.
2. Fix our I/O loop to rotate through fds and deferred tasks, so yield is fair.
3. Yielding on plugin reply RPC too, which definitely helps.
4. Hooks can now specify an array of filter strings: for the command hook, these are the commands you're interested in.
As a result, my hand-written sleep1/lightning-cli help test spikes at 44ms, not 110 seconds!
My next steps are to use synthetic data (say, 10M records to allow for future growth) and formalize latency measurements into our CI.
Next release looking amazing!
I think finding a bug where printf("%*.s") was used instead of printf(".*s") was the point at which I realized that some C issues cannot be mitigated with better tooling...
I had way too much fun optimizating CLN due to a Boltz report recently. Like most engineers, I love optimizing, but bitter experience means I only allow myself to do so when I have an actual problem to solve.
My favourites:
1. Adding 1M entries to a sqlite3 table with two indexes: 81 seconds. Adding entries *then* creating indices: 17 seconds.
2. Optimization of O(nĀ²) cleanup code by realizing it could be deleted entirely.
I admit I continued to optimize long after their performance problem was fixed, but you gotta have *some* fun!
I hate price talk, but if you're going to do it, please understand that "market cap" is a very rough *ceiling* on current value.
It's neither the amount of money which has gone in, nor the amount of money which can come out.
So the order of magnitude is useful to compare against other assets. But abusing it in terms of profits and losses is a category error, and I assume done mainly because it's so easy to measure.
Grump over.
In two days' time Julian and I will be doing an open Jitsi meeting to discuss the work on Script Restoration. Come and ask questions!
1pm Berlin time:
https://www.timeanddate.com/worldclock/meetingdetails.html?year=2025&month=10&day=15&hour=11&min=0&sec=0&p1=5&p2=37I needed some code in a third place, so I decided to extract the ~100 lines it into a single function in common code (and make it more efficient, because I had seen it in profiles under stress testing).
I often write code by starting it and seeing where it leads: this is helped by modern revision control and fast compile times (I point this out because we take these for granted).
First extraction went fine. Then I tried to use the same code in the second place. By the time I'd had to add four callback hooks (three of which were unneeded in the first case) I stopped. The code was different enough that the "framework with callbacks" made the code far *less* clear.
Threw it away, in favor of a handful of helper routines. More code for the first case, but much more natural for the second.
This took a day, on and off. But the off was important: the breaks gave me time to ask "now it's almost finished, do I like it?" and avoid being too goal driven.
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I'm going to do an open hour on the Script Restoration BIPs: All questions welcome, even (especially!) if you're not a developer.
About 24 hours from now (I'll comment with the Jitsi link)
https://www.timeanddate.com/worldclock/meetingdetails.html?year=2025&month=10&day=4&hour=22&min=0&sec=0&p1=5&p2=224&p3=37&iv=1800Should I run open hours for the script BIPs? Like, one a week for four weeks, you can show up and ask questions and I'll try to answer?
That might help me get a feel for what is unclear or confusing.
If so, what platform do I use? Never done anything like this before š¬
Finally posted the 4 script restoration BIPs to the mailing list.
Sorry it's taken so long!
I strongly suspect that the bitcoin experience, even for veterans, will be quite different in ten years.
BIP 353 brings names: ACINQ have a spec for supporting contact lists too. I expect vanity addresses to follow as providers get onboard.
Silent payment addresses should replace all other on-chain addresses, especially deposit to exchanges. Though you'll probably just send to e.g. <acctname>@client.river.com (will this allow probing of account names? Will they use random ones instead? Or accept anything and if they get typo payments sort it out in customer service?)
And BOLT12 provides reusable lightning addresses, which provide the off-chain analog of silent payments. Doesn't matter to you if the recipient is using some weird layer 2, either. BIP 353 returns both this and a silent payment address, so the sender wallet chooses.
It's been two years since the twenty-weeks-of-friends-coming-over that was Pandemic Legacy. Now the second edition of Gloomhaven has arrived, and we are planning another epic:
If you haven't played this kind of thing before: the game is a progressive cooperative affair, designed to be played in two(?) hour long sessions. Obviously there are weeks you miss, but the overall experience is a season or two of regular game play. There are highs and lows as things twist and turn, and I always feel the discomfort of doing something complex and unfamiliar, but overall it's about shared experience.
Must get the script BIP drafts published *before* we start this!
