Top all-time · #17814
Luna Nova
Personal blog · lunnova.dev/articlessystemsprogramminghardware
Luna Nova's personal blog at lunnova.dev covers systems, programming and hardware. Since 2022, 4 different Hacker News readers have linked it 10 times, most often “Zen 3's Slow Short Rep Mov”. It is still writing: the last post was on 2026-09-06, and you can follow it by feed.
Too few sampled comments (1) to say how often HN recommends it.?
Why HN links it
Linked in a thread on CPU data-movement performance. The one comment quotes the post's question about memcpy on the 68000 and gives a history of CPU fast paths for moving data, such as rep movsw and the W65C816 MVN/MVP instructions.
Summarised by Claude from a sample of 1 HN comments that link here. Each comment is marked recommending, critical or neutral (citing without judging); how this works.
Luna Nova's site. GPGPU compute & build systems, Rust, hardware hacking, opinion pieces.
Most-linked posts?
- Zen 3's Slow Short Rep Mov2 people · 2 mentions · first linked 2024-02-15
- ROCm 7.1.1: you can (not) build2 people · 2 mentions · first linked 2026-02-23
What Hacker News says?
>unoptimized memcpy could anyone do any better on 68000? My incomplete history of CPU dedicated fast paths for moving data: - 1982 Intel 186/286 'rep movsw' at theoretical 2 cycles per byte (I think its closer to 4 in practice). Brilliant, then intel drops the ball for 20 years :| - 1986 WDC W65C816 Move Memory Negative (MVN), Move Memory Positive (MVP) at hilarious 7 cycles per byte. Slower than unrolled code, 2x s…
Comment linking /articles/ryzen-slow-short-rep-mov/
on “AMD Disables Zen 4's Loop Buffer”Submitted Crawler operators, please stop destroying the commons as a story · 7 points
HN discussionThe article itself reads as an AI generated output, complete with classic Not Just X … Y hallmarks from forever ago, 100% on pangram's low false positive detector. I'm not sure if it's some experiment on their readerbase or what. pangram result: https://www.pangram.com/history/02bead1c-c36e-461b-8fa7-8699... So many AI generated AI bashing articles lately. I wrote a post complaining about running into these, and ask…
Comment linking /articles/ai-bashing-ai-slop/
on “Why AI writing is so generic, boring, and dangerous: Semantic ablation”Submitted AI generated posts about AI failures (keep showing up on HN) as a story · 3 points
HN discussionSubmitted Migrating Primary Drive on NixOS as a story · 3 points
HN discussionSubmitted ROCm 7.1.1: you can (not) build as a story · 2 points
HN discussionSubmitted ROCm 7.1.1: you can (not) build as a story · 2 points
HN discussionSubmitted Pattern-wishcast: enum pattern types in 2025 rust as a story · 1 points
HN discussionSubmitted Zen 3's Slow Short Rep Mov as a story · 1 points
HN discussionSubmitted Google removed my Yubikeys “Just to be safe” as a story · 1 points
HN discussion