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OpenAI Backs Bill That Would Limit Liability for AI-Enabled Mass Deaths

https://www.wired.com/story/openai-backs-bill-exempt-ai-firms-model-harm-lawsuits/
210•smurda•1h ago•124 comments

Intel 486 CPU announced April 10, 1989

https://dfarq.homeip.net/intel-486-cpu-announced-april-10-1989/
77•jnord•2h ago•53 comments

Protected quantum gates using qubit doublons in dynamical optical lattices

https://ethz.ch/en/news-and-events/eth-news/news/2026/04/a-new-trick-brings-stability-to-quantum-...
179•joko42•10h ago•39 comments

Mysteries of Dropbox: Property-Based Testing of a Distributed Sync Service [pdf]

https://www.cis.upenn.edu/~bcpierce/papers/mysteriesofdropbox.pdf
10•JackeJR•2d ago•2 comments

How NASA built Artemis II’s fault-tolerant computer

https://cacm.acm.org/news/how-nasa-built-artemis-iis-fault-tolerant-computer/
474•speckx•22h ago•184 comments

FBI used iPhone notification data to retrieve deleted Signal messages

https://9to5mac.com/2026/04/09/fbi-used-iphone-notification-data-to-retrieve-deleted-signal-messa...
175•01-_-•2h ago•79 comments

Show HN: QVAC SDK, a universal JavaScript SDK for building local AI applications

8•qvac•18h ago•0 comments

France Launches Government Linux Desktop Plan as Windows Exit Begins

https://www.numerique.gouv.fr/sinformer/espace-presse/souverainete-numerique-reduction-dependance...
723•embedding-shape•3h ago•332 comments

I still prefer MCP over skills

https://david.coffee/i-still-prefer-mcp-over-skills/
297•gmays•12h ago•249 comments

White House staff told not to place bets on prediction markets

https://www.bbc.co.uk/news/articles/cgld65x396go
97•chrischapman•2h ago•51 comments

Native Instant Space Switching on macOS

https://arhan.sh/blog/native-instant-space-switching-on-macos/
568•PaulHoule•18h ago•273 comments

Model-Based Testing for Dungeons & Dragons

https://www.loskutoff.com/blog/model-based-testing-dnd/
66•Firfi•3d ago•18 comments

Artemis II and the invisible hazard on the way to the Moon

https://www.ansto.gov.au/news/artemis-ii-and-invisible-hazard-on-way-to-moon-part-1
50•zeristor•7h ago•39 comments

Penguin 'Toxicologists' Find PFAS Chemicals in Remote Patagonia

https://www.ucdavis.edu/health/news/penguin-toxicologists-find-pfas-chemicals-remote-patagonia
62•giuliomagnifico•7h ago•15 comments

Show HN: Keeper – embedded secret store for Go (help me break it)

https://github.com/agberohq/keeper
43•babawere•5h ago•25 comments

Show HN: Marimo pair – Reactive Python notebooks as environments for agents

https://github.com/marimo-team/marimo-pair
51•manzt•2d ago•4 comments

We've raised $17M to build what comes after Git

https://blog.gitbutler.com/series-a
213•ellieh•12h ago•457 comments

Generative art over the years

https://blog.veitheller.de/Generative_art_over_the_years.html
196•evakhoury•2d ago•48 comments

Charcuterie – Visual similarity Unicode explorer

https://charcuterie.elastiq.ch/
270•rickcarlino•17h ago•62 comments

The Art of Risk Management (2017)

https://www.bcg.com/publications/2017/finance-function-excellence-corporate-development-art-risk-...
32•walterbell•2d ago•9 comments

CollectWise (YC F24) Is Hiring

https://www.ycombinator.com/companies/collectwise/jobs/Ktc6m6o-ai-agent-engineer
1•OBrien_1107•9h ago

RAM Has a Design Flaw from 1966. I Bypassed It [video]

https://www.youtube.com/watch?v=KKbgulTp3FE
308•surprisetalk•2d ago•110 comments

Old laptops in a colo as low cost servers

https://colaptop.pages.dev/
341•argentum47•19h ago•195 comments

The effects of caffeine consumption do not decay with a ~5 hour half-life

https://www.lesswrong.com/posts/vefsxkGWkEMmDcZ7v/the-effects-of-caffeine-consumption-do-not-deca...
12•swah•32m ago•5 comments

Ads in ChatGPT

https://help.openai.com/en/articles/20001047-ads-in-chatgpt
11•cbility•3h ago•2 comments

Unfolder for Mac – A 3D model unfolding tool for creating papercraft

https://www.unfolder.app/
276•codazoda•21h ago•54 comments

Instant 1.0, a backend for AI-coded apps

https://www.instantdb.com/essays/architecture
182•stopachka•19h ago•90 comments

Kagi Product Tips – Customize Your Search Results with URL Redirects

https://blog.kagi.com/tips/redirects
133•treetalker•16h ago•27 comments

Research-Driven Agents: When an agent reads before it codes

https://blog.skypilot.co/research-driven-agents/
193•hopechong•21h ago•51 comments

PicoZ80 – Drop-In Z80 Replacement

https://eaw.app/picoz80/
211•rickcarlino•19h ago•32 comments
Open in hackernews

Pglocks.org

https://pglocks.org/
80•hnasr•10mo ago

Comments

whilenot-dev•10mo ago
I'm a bit lost here.

Locking is a challenging problem in complex systems. Is this list to be interpreted as a "TODO: get rid of locking conflicts in future releases" or more a "NOTE: be aware there are known conflicts that will not change - find ways to work around them"?

EDIT: Also, is the creation of this list an automated or a manual effort?

tux3•10mo ago
I think this is intended as educational material, not a list of things to fix.

The locks are here by necessity, it is not so easy at all to get rid of them. And even in special cases where it is possible, the complexity you have to introduce is not to be taken lightly...

If even a tenth of these disapppeared, it would be incredible, in a very surprising way.

atombender•10mo ago
The creator looks like a developer and teacher, not a Postgres core team member. So I assume this is for documentation purposes.

I actually like this a lot, as there isn't a single place in the Postgres documentation that lists all the possible locks; it's spread out all over. Having a quick reference for what kinds of commands you'd be blocking with your transaction is valuable.

It's pretty evident that the pages have been programmatically generated, but I'd love know what it's generated from. I think you can derive this information from the documentation, but not sure if you can do it in an automated way without an LLM.

braiamp•10mo ago
> there isn't a single place in the Postgres documentation that lists all the possible locks

Did you read this page? https://www.postgresql.org/docs/current/explicit-locking.htm...

atombender•10mo ago
That's a great page, but it has several issues.

First, it isn't complete; as I said, the locking behaviour is spread out all over the Postgres documentation. For example, that page doesn't list what locks DROP INDEX takes. To find that out, you have to go to the documentation page for that command and read it carefully. In fact, really carefully — the locking behaviour is only documented under the section about CONCURRENTLY.

The page also doesn't list what possible commands are then blocked. Locks interact in subtle (and incorrectly named!) ways that are explained in the tables on that page ("Conflicting lock modes"), so to understand if something will block something else you have to look at the two commands you are curious about and then look at how their locks interact.

gulcin_xata•10mo ago
I agree, it is not so straightforward to find out.
braiamp•10mo ago
These are database locks, which means that depending which arrives first, the later transaction has to wait till the first one finishes to complete. These locks are about SQL commands and which commands can run concurrently with the others. There's a graph here of how that looks like https://pankrat.github.io/2015/django-migrations-without-dow...

Usually for maximum performance (minimum latency, maximum throughput) you want to have operations not lock each other, unless absolutely necessary, in which case you want them to be short.

whilenot-dev•10mo ago
You make it sound like the conflict is just affecting performance and won't result in a deadlock. So it's for performance aware postgres clients/users, and not for postgres developers?
andyferris•10mo ago
It is a guide for developers using postgres as a client, who need to write systems that don't deadlock, are performant and are correct. These are the (rather sharp) tools that postgres provides for doing so (or else you can use e.g. serializable isolation and optimistic concurrency, but in my experience that has too many false positives and bail out rather eagerly, whereas these tools let you be very precise and granular).
mebcitto•10mo ago
Other relevant talks/blogs that I found really useful for understanding Postgres locks are:

* Unlocking the Postgres Lock Manager by Bruce Momjian: https://momjian.us/main/writings/pgsql/locking.pdf

* Anatomy of table-level locks by Gulcin Yildirim Jelinek: https://xata.io/blog/anatomy-of-locks

pasxizeis•10mo ago
Shameless plug: I wrote a tool[1] that executes a given migration against a test database (e.g. in your CI) and reports back what locks it acquired.

The rationale being to have a "lock diagnostics report" commented in your PR's migration file.

It's a prototype and has a few rough edges and missing functionality, but feedback is more than welcome.

[1] https://github.com/agis/pglockanalyze

jononor•10mo ago
Very practical! Locking is one of the things that can really bite when doing migrations.