Post Syndicated from original https://lwn.net/Articles/879724/rss

When the goal is to push bits over the network as fast as the hardware can
go, any overhead hurts. The cost of copying data to be transmitted
from user space into the kernel can be especially painful; it adds latency,
takes
valuable CPU time, and can be hard on cache performance. So it is
unsurprising that the developers working with io_uring, which is all about performance, have
turned their attention to zero-copy network transmission. This
patch set from Pavel Begunkov, now in its second revision, looks to be
significantly faster than the MSG_ZEROCOPY option supported by current
kernels.