Evgeniy Polyakov wrote: >> This is what Xen does. It is actually less performant than copying, IIRC. >> >> The problem with flipping pages around is that physical addresses are >> cached both in the kvm mmu and in the on-chip tlbs, necessitating >> expensive page table walks and tlb invalidation IPIs. >> > > Hmm, I'm not familiar with Xen driver, but similar technique was used > with zero-copy network sniffer some time ago, substituting userspace > pages with pages containing skb data was about 25-50% faster than > copying 1500 bytes in general, and in order of 10 times faster in some > cases. > > Check a link please in case we are talking about different ideas: > http://marc.info/?l=linux-netdev&m=112262743505711&w=2 > >
I don't really understand what you're testing there. in particular, how can the copying time change so dramatically depending on whether you've just rebooted or not? -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
