Definitely too general of a statement. I previously worked on real-time mapping and the only way to get the necessary write performance was to go unbuffered and

Definitely too general of a statement. I previously worked on real-time mapping and the only way to get the necessary write performance was to go unbuffered and manually split off a block at a time to write. The same was true of reading - it was faster and made sure the # of syscalls in any frame was predictable. As a side note, the real issue here is that unbuffered is the default. Other languages and libraries I’m aware of make it difficult to get in such a mode.