On Sat, Nov 2, 2019 at 11:50 PM Pravin Shelar <[email protected]> wrote: > > On Fri, Nov 1, 2019 at 7:24 AM <[email protected]> wrote: > > > > From: Tonghao Zhang <[email protected]> > > > > The full looking up on flow table traverses all mask array. > > If mask-array is too large, the number of invalid flow-mask > > increase, performance will be drop. > > > > One bad case, for example: M means flow-mask is valid and NULL > > of flow-mask means deleted. > > > > +-------------------------------------------+ > > | M | NULL | ... | NULL | M| > > +-------------------------------------------+ > > > > In that case, without this patch, openvswitch will traverses all > > mask array, because there will be one flow-mask in the tail. This > > patch changes the way of flow-mask inserting and deleting, and the > > mask array will be keep as below: there is not a NULL hole. In the > > fast path, we can "break" "for" (not "continue") in flow_lookup > > when we get a NULL flow-mask. > > > > "break" > > v > > +-------------------------------------------+ > > | M | M | NULL |... | NULL | NULL| > > +-------------------------------------------+ > > > > This patch don't optimize slow or control path, still using ma->max > > to traverse. Slow path: > > * tbl_mask_array_realloc > > * ovs_flow_tbl_lookup_exact > > * flow_mask_find > > > > Signed-off-by: Tonghao Zhang <[email protected]> > > Tested-by: Greg Rose <[email protected]> > > --- > Acked-by: Pravin B Shelar <[email protected]>
Nack to this patch. It makes the mask cache invalid when moving the flow mask to fill another hole. And the penalty for miss the mask cache is larger than the benefit of this patch (avoiding the NULL flow-mask). William _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
