On Tue, 31 Jan 2017 16:31:57 +0100 Nikolay Aleksandrov <niko...@cumulusnetworks.com> wrote:
> Fdb's used and updated fields are written to on every packet forward and > packet receive respectively. Thus if we are receiving packets from a > particular fdb, they'll cause false-sharing with everyone who has looked > it up (even if it didn't match, since mac/vid share cache line!). The > "used" field is even worse since it is updated on every packet forward > to that fdb, thus the standard config where X ports use a single gateway > results in 100% fdb false-sharing. Note that this patch does not prevent > the last scenario, but it makes it better for other bridge participants > which are not using that fdb (and are only doing lookups over it). > The point is with this move we make sure that only communicating parties > get the false-sharing, in a later patch we'll show how to avoid that too. > > Signed-off-by: Nikolay Aleksandrov <niko...@cumulusnetworks.com> > --- What about making updated a per-cpu value?
