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Reduce allocation in Go code

• Animats 12y ago
  Go does many small allocations behind the scenes. A "select" with more than one case does some allocation. The Go compiler generates special-case code for a single-case select. More than one case uses a complicated N-case library function that does some allocation. Passing a parameter as an "interface{}", or creating a slice, also causes the creation of temporary objects, which are usually (always?) on the heap. This may or may not be a big problem depending on how the allocator and garbage collector work. Anyone know?
• tptacek 12y ago
  FWIW: If you're working with strings gradually built out of other strings, the Golang idiom is bytes.Buffer, to which you write strings as if to a file. It's the Golang equivalent of building an array of strings in Python and join()ing it.
  • kevin_thibedeau 12y ago
    And how does this work when Unicode combining characters come into play?
    • tptacek 12y ago
      I'm not sure I see the problem. You can safely write a utf-8 string to a bytes.Buffer.
    • pkulak 12y ago
      You just need to remember that they are UTF-8 encoded when they come back out.