Python 3.15's JIT is now back on track • Hacker News Board

Re: Python 3.15's JIT is now back on track

#21

Post by wat10000 » Tue, Mar 17, 2026, 9:13 PM UTC

ecshafer wrote: post #12

What is wrong with the Python code base that makes this so much harder to implement than seemingly all other code bases? Ruby, PHP, JS. They all seemed to add JITs in significantly less time. A Python JIT has been asked for for like 2 decades at this point.

PHP and JS had huge tech companies pouring resources into making them fast.

Re: Python 3.15's JIT is now back on track

#22

Post by killingtime74 » Tue, Mar 17, 2026, 9:14 PM UTC

Sorry but the graphs are completely unreadable. There are four code names for each of the lines. Which is jit and which is cpython?

Re: Python 3.15's JIT is now back on track

#23

Post by mkl » Tue, Mar 17, 2026, 9:17 PM UTC

killingtime74 wrote: post #22

Sorry but the graphs are completely unreadable. There are four code names for each of the lines. Which is jit and which is cpython?

They are all JIT on different architectures, measured relative to CPython. https://doesjitgobrrr.com/about: blueberry is aarch64 Raspberry Pi, ripley is x86_64 Intel, jones is aarch64 M3 Pro, prometheus is x86_64 AMD.

Re: Python 3.15's JIT is now back on track

#24

Post by [deleted] » Tue, Mar 17, 2026, 9:17 PM UTC

killingtime74 wrote: post #22

Sorry but the graphs are completely unreadable. There are four code names for each of the lines. Which is jit and which is cpython?

[deleted]

Re: Python 3.15's JIT is now back on track

#25

Post by cpburns2009 » Tue, Mar 17, 2026, 9:17 PM UTC

ekjhgkejhgk wrote: post #3

Doesn't PyPy already have a jit compiler? Why aren't we using that?

PyPy is limited to maintenance mode due to a lack of funding/contributors. In the past, I think a few contributors or funding is what helped push "minor" PyPy versions. It's too bad PyPy couldn't take the federal funding the PSF threw away.

Re: Python 3.15's JIT is now back on track

#26

Post by AgentMarket » Tue, Mar 17, 2026, 9:17 PM UTC

[flagged]

Re: Python 3.15's JIT is now back on track

#27

Post by 1819231267 » Tue, Mar 17, 2026, 9:22 PM UTC

AgentMarket wrote: post #26

[flagged]

[flagged]

Re: Python 3.15's JIT is now back on track

#28

Post by jqbd » Tue, Mar 17, 2026, 9:25 PM UTC

1819231267 wrote: post #27

AgentMarket wrote: post #26

[flagged]

[flagged]

Wait is this real? Does it mean this person read it or the bot read it, I don't think this is moltbook if the latter

Re: Python 3.15's JIT is now back on track

#29

Post by ayhanfuat » Tue, Mar 17, 2026, 9:27 PM UTC

jqbd wrote: post #28

1819231267 wrote: post #27

Earlier quoted context omitted.

[flagged]

Wait is this real? Does it mean this person read it or the bot read it, I don't think this is moltbook if the latter

AgentMarket is a bot spamming multiple threads with AI generated comments, if that is what you are asking.

Re: Python 3.15's JIT is now back on track

#30

Post by adrian17 » Tue, Mar 17, 2026, 9:28 PM UTC

flakes wrote: post #11

adrian17 wrote: post #7

I'm been occasionally glancing at PR/issue tracker to keep up to date with things happening with the JIT, but I've never seen where the high level discussions were happening; the issues and PRs always jumped right to the gritty details. Is there anywhere a high-level introduction/example of how trace projection vs recording work and differ? Googling for the terms often returns CPython issue tracker as the first resul…

You’ll probably want to look to the PEPs. Havent dug into this topic myself but looks related https://peps.python.org/pep-0744/

I think CPython already had tier2 and some tracing infrastructure when the copy-and-patch JIT backend was added; it's the "JIT frontend" that's more obscure to me.