NewNativeCompactionFilter useful due to slow CGO calls?

[Jim Plush]

Can I assume that NewNativeCompactionFilter is in place to allow for a C based implementation of a CompactionFilter due to the fact using the CompactionFilter interface in a Go based filter is extremely slow due to the CGO overhead of calling that Filter for every key you want to potentially filter out?

If that's the case, are there any known examples in the wild or snippets for implementing the C filter in the wild?

thanks!