dominikbraun / haystack Goto Github PK

When a file buffer (which is a Vec<u8>) isn't needed anymore, there are 2 options:

Re-use the buffer and grow it only if required

In this case, the buffer is initialized once with Vec::new() before the loop starts and the buffer is filled. To keep memory usage small, shrink_to_fit() has to be invoked if the allocated space is no more needed.

Re-initialize the buffer in each iteration

In this situation, Vec::new() is called in every iteration and - if there aren't any optimizations - the space will be reallocated each time.

It must be clarified which method is faster when running ten of thousands iterations. In case the shrinking buffer version has better performance, at which memory size should it trigger?