# Go 1.24 Map Redesign: Swiss Tables Revolution How was map structure optimized in Go? - **Source:** [programming](https://brifing.si/source/21f413d8-a401-41ca-83b1-904b87bb8257) - **Published:** 2026-07-24 - **Topic:** [Software & Engineering](https://brifing.si/c/engineering) - **Original article:** - **On Brifing:** https://brifing.si/s/f41d04e1-292b-48e3-99e2-5c5013e759cf ## How Did Map Design Change in Go 1.24? Go 1.24 transitioned its map structure from the classic bucket + overflow-chain model to a Swiss Table-inspired design. This change significantly impacted memory efficiency and performance. ## Problems with the Old Map Design In the old design, pointer-chasing harmed cache locality, leading to performance losses, especially with large datasets. ## Advantages of Swiss Tables Swiss Tables optimize lookup behavior using control bytes and h2 filtering. This improves practical load factor and makes memory usage more efficient. ## Go-Specific Constraints Go’s map design is shaped by unique constraints like iteration semantics, GC/runtime integration, and incremental growth behavior. These factors influence design decisions. ## Performance Comparison Microbenchmark tests show significant gains, while full-application tests reveal smaller improvements. This highlights how the design performs in different scenarios. ## Future Improvements Work continues in areas like cold-cache and certain delete/clear operations. This indicates that Go’s map design will be further optimized in the future. ## Sources covering this story - https://www.reddit.com/r/programming/comments/1v58vch/golang_maps_how_swiss_tables_replaced_the_old/ — --- _Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._