> Could you define unacceptable performance drop? Have you tried to measure > what would be the impact?
> I know it can be bad, depending on the class of protocols. I think that > if numbers were provided to demonstrate that bounce buffers (the swiotlb > in Linux) are too slow for a given use case Unfortunately I could not come up with exact requirements numbers. Introducing another memcpy (what bouncing buffer approach does) for block or network IO would not only reduce the operation performance but also increase the overall system load. All what we does for any of our PV driver solutions is avoiding data copying inside FE-BE pair in order to increase performance, reduce latency and system load. Sincerely, Andrii Anisov. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org https://lists.xen.org/xen-devel
