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jashmatthewson Show HN: PgQueuer – Transform PostgreSQL into a Job Queue

Putting low throughput queues in the same DB is great both for simplicity and for getting exactly-once-processing.

Putting high throughput queues in Postgres sucks because...

No O(1) guarantee to get latest job. Query planner can go haywire.

High update tables bloat like crazy. Needs a whole new storage engine aka ZHEAP

Write amplification as every update has to update every index

LISTEN/NOTIFY doesn't work through connection pooling

jashmatthewson GIL Become Optional in Python 3.13

It's the sledgehammer approach but... Docker?

jashmatthewson Porsche Design System v3

Late 80s early 90s Corollas were very popular first track day cars in Australia and New Zealand. A standard AE92 Corolla FX-GT will happily go on a track day as long as it has fresh brake fluid. I've done it!

jashmatthewson Porsche Design System v3

There are plenty of older Corollas you can use on a track day. My AE92 did fine for a few laps.

jashmatthewson Mir: Strongly typed IR to implement fast and lightweight interpreters and JITs

> TRYD (Trace Rewriter Yielding Dynamics): reconstitutes a CFG from traces in order to not only JIT single hot paths but also multiple interlacing warm ones

Do you have more information on that? Googling didn't turn much up. It sounds similar to the Trace Tree or region based compilation approaches?

jashmatthewson Choose Postgres queue technology

Sidekiq will drop in-progress jobs when a worker crashes. Sidekiq Pro can recover those jobs but with a large delay. Sidekiq is excellent overall but it’s not suitable for processing critical jobs with a low latency guarantee.

https://github.com/sidekiq/sidekiq/wiki/Reliability

jashmatthewson Nobody ever paid me for code

Engineering output doesn't even scale close to linearly, though. You _might_ grow revenue 1.5x but now you have 3x as much code/system and need 6-9x as the engineering headcount.

We probably just took a nice small/medium profitable business and completely fucked it.

jashmatthewson People who've received a black bar on Hacker News

Chris Seaton should have got one

jashmatthewson Ways to shoot yourself in the foot with Postgres

The defaults do suck but common storage options like SSDs or Elastic Block Storage still do sequential IO substantially faster than random.

jashmatthewson GitHub Copilot investigation

Doesn't Copilot reproduce the exact expression given the right prompt, though?

jashmatthewson Faster CPython (2021) [pdf]

Shopify got to huge scale first and then started sponsoring TruffleRuby and YJIT as research projects.

jashmatthewson Unvaccinated workers who lose jobs ineligible for unemployment benefits (Canada)

> It is an unfortunate misconception that any of the currently-approved intramuscular vaccines reduce transmission to a meaningful degree.

This is another misconception. Our best evidence is that they're extremely effective. The problem is they're not quite effective enough to just go back to life as before since newer variants are extremely virulent.

jashmatthewson Unvaccinated workers who lose jobs ineligible for unemployment benefits (Canada)

It's dramatically effective in reducing spread. Unvaccinated people are driving 85-90% of the spread in Germany. https://rocs.hu-berlin.de/publication/maier-2021-germany/

jashmatthewson Locked-out New Zealanders outraged as visa scheme for rich foreigners resumes

In NZ the normal way is Comparative Value which taxes the increase in market value when you sell.

Fair Dividend Rate isn't a wealth tax. It's a frankly bullshit option rich people can use when their investments do really well to cap the tax owed to 5% of the starting market value.

Hatch explain it a bit here: https://www.hatchinvest.nz/learn-articles/tax-50000-fif

jashmatthewson From Node to Ruby on Rails

The solution you're looking for is Docker. Gitlab distributes as a Docker image.

jashmatthewson Germany locks down unvaccinated people, as leaders plan to make shots compulsory

In Germany, the majority of the cases are from unvaccinated people getting sick and infecting other people

https://rocs.hu-berlin.de/publication/maier-2021-germany/

jashmatthewson Germany locks down unvaccinated people, as leaders plan to make shots compulsory

Vaccinated people don’t transmit as much, nor are they as likely to contract the virus. Current estimates are 85-90% of transmission in Germany involves someone unvaccinated

https://rocs.hu-berlin.de/publication/maier-2021-germany/

jashmatthewson Tech investors can’t get enough of Europe’s fizzing startup scene

Paying private health insurance and pension is, inalmost all cases, better for an internationally mobile founder anyway!

jashmatthewson Merge YJIT: an in-process JIT compiler

> the actual JIT is only a couple of thousands of lines of C

Even for Ruby, a basic JIT can be implemented in a few hundred lines of C using a "threaded code" approach.

Real JIT compilers got started this way. Safari JavaScriptCore's JIT used a "context threaded code" approach and was just 4k LOC

https://webkit.org/blog/214/introducing-squirrelfish-extreme...

jashmatthewson Index bloat reduced in PostgreSQL v14

Because the contents of the table is changing the statistics are becoming out of date.

jashmatthewson Index bloat reduced in PostgreSQL v14

Tune autovacuum analyze to run every 30mins. Seriously. The query planner needs up to date statistics.

jashmatthewson Fullstaq Ruby: Ruby, optimized for production

jemalloc isn’t a special allocator. It’s basically the FreeBSD default.

jashmatthewson PostgreSQL, Memory and the Cloud

THP is a net loss for many workloads, including PG https://www.percona.com/blog/2019/03/06/settling-the-myth-of...

For workload using forking and CoW sharing like Redis or CRuby it negates the entire benefit of CoW since flipping a single bit copies the entire huge page.

jashmatthewson Why Is JRuby Slow?

The Truffle based implementations of dynamic languages get close depending on what you’re benchmarking.

https://stefan-marr.de/papers/dls-marr-et-al-cross-language-...

jashmatthewson Why Is JRuby Slow?

The Ruby community continues to grow in absolute terms of you’re looking at conference numbers etc. The rest of the industry exploded!

jashmatthewson Why Is JRuby Slow?

Crystal is little like Ruby now.

jashmatthewson Cinder: Instagram's performance-oriented fork of CPython

> Sadly not much progress has been made on the RubyVM

Lots of progress has been made on CRuby. The official optcarrot benchmark (realistic-ish interpreter bound) is ~6x faster on Ruby 2.6 than Ruby 1.8.

CRuby performance running Rails improved almost as much. Zendesk got a 2-3x improvement from 1.8 to 1.9 and 1.9 to 2.6 doubles it again.

jashmatthewson Cinder: Instagram's performance-oriented fork of CPython

Enormously. The latest Railsbench results on TruffleRuby are ~3x CRuby.

jashmatthewson Parsing Protobuf at 2+GB/S: How I Learned to Love Tail Calls in C

Even more wild is the JavaScriptCore bytecode VM which is written in a Ruby DSL which is either compiled to C or directly to ASM.

I'm jealous we don't have something like this for CRuby!