Maybe. It depends on whether or not the kernel is smart enough to recognize that the pages you&#x27;ve referenced in the AIO operation are pages are mmap&#x27;d files rather than ordinary heap memory. It would need to do some amount of page table walking to learn that, but certainly for a large enough operation that would be cheaper than simply making the copy.<p>I suspect that Linux, at least, does not do this. That said, I&#x27;m curious about the difficulty of plumbing such an optimization. Unfortunately due to other implementation details of the networking stack I work on day to day it wouldn&#x27;t have any implications for that, but it might have some for one of my side projects.