SWAR

Discussion: Reddit (r/java) · Hacker News This is Part 3 of a series on building a high-performance hash table for the JVM. Part 1 — Building a Fast, Memory-Efficient Hash Table in Java (by borrowing the best ideas): designing a SwissTable-style map from scratch — control bytes, SWAR probing, and why open addressing beats chaining for cache locality. Part 2 — Further Optimizing my Java SwissTable: Profile Pollution and SWAR Probing: hunting down a surprising Objects.equals() hotspot, and why SWAR beat the Vector API on both ARM and x86. Part 3 (this post): handing the profiler to an AI agent — and what it found. Part 3: letting the agent drive At the end of the last post, I had a SwissMap that felt genuinely fast: the Objects.equals() profile pollution was gone, SWAR had beaten the Vector API on both ARM and x86, and I finally had benchmarks I was willing to trust. ...

Discussions Reddit Part 2: optimizing the hot path (and finding a weird villain) “Why Objects.equals() showed up in the profile—and why SWAR beat the Vector API on ARM (and x86). In the last post, I finally got a SwissTable-ish map running on the JVM and fast enough to make me smile. Naturally, that meant I immediately started staring at the profiler again, thinking: okay… but how do I make it faster? ...