Hash tables in Go and advantage of self-hosted compilers
2 days ago
- #Memory Optimization
- #Compiler
- #Go
- Go uses `map[int]bool` or `map[int]struct{}` to track unique values due to the absence of a set data structure.
- Using `map[int]struct{}` was believed to save memory because `struct{}` is a zero-sized type, but this is not the case in Go 1.24+ due to the new Swiss Tables implementation.
- The Go compiler adds padding to ensure proper memory alignment, making `struct{}` and `bool` consume the same amount of memory (1 byte).
- Prior to Go 1.24, `map[int]struct{}` saved memory because keys and values were stored in separate arrays, and the values array could be omitted for empty structs.
- Self-hosted compilers, like Go's, are written in the same language they compile, making the source code easier to understand and modify.
- The article emphasizes not to blindly trust LLMs and to verify information, especially regarding compiler optimizations and memory usage.