← Wednesday, October 7, 2026Performance & OSDeep dive

Linux x32 cut a Mastodon deployment’s memory use from 650 MB to 350 MB

alexalejandre.com 13 min read Editor score 7/10

The x32 ABI uses 32-bit pointers on 64-bit systems; the author reports Mastodon memory use falling from 650 MB to 350 MB. It shows a practical memory trade-off for pointer-heavy software, alongside the friction of limited packaging.

What

The Linux x32 ABI uses 32-bit pointers on 64-bit systems; the author reports Mastodon memory use falling from 650 MB to 350 MB.

How

A Janet test on Arch reported 20% lower memory use but 50% slower performance with x32.

Why it matters

Smaller pointers can reduce memory use and improve cache fit for pointer-heavy heaps, but limited packaging means building much of the software yourself.

Read on alexalejandre.com → Lobsters · 7 comments

Headline, summary, brief and diagram are written by a model from the source's own text; the link, byline and numbers come from the source. Read the original before relying on a claim.