What cross-cache copy?
When we're talking really high performance, we're talking DMA and cards
that do the checksum on the card themselves. In that case the data never
even touches the caches on the CPU that takes the interrupt - or at least
only the headers for finding out what the packet is all about.
> The header can be in multiple parts. Also stuff like the NFS rpc code would
> need a rewrite to cope with fragmented rpc headers
I certainly agree on the need to have the headers in one fragment, but
that still doesn't mean we need to reassemble _all_ fragments.
Linus