On Fri, Jan 6, 2017 at 8:48 AM, Eric Dumazet <eduma...@google.com> wrote: > On Fri, Jan 6, 2017 at 8:31 AM, Vlastimil Babka <vba...@suse.cz> wrote: > >> >> I wonder what's that cause of the penalty (when accessing the vmapped >> area I suppose?) Is it higher risk of collisions cache misses within the >> area, compared to consecutive physical adresses? > > I believe tests were done with 48 fq qdisc, each having 2^16 slots. > So I had 48 blocs,of 524288 bytes. > > Trying a bit harder at setup time to get 128 consecutive pages got > less TLB pressure.
Forgot to mention tests include DDOS, so hitting a random hash bucket for every packet.
