RE: GRO aggregation

On Tue, 2012-09-11 at 19:24 +0000, Shlomo Pongratz wrote:

I see that in ixgbe the weight for the NAPI is 64 (netif_napi_add). So
if packets are arriving in high rate then an the CPU is fast enough to
collect the packets as they arrive, assuming packets continue to
arrives while the NAPI runs. Then it should have aggregate more. So we
will have less passes trough the stack.

As I said, _if_ your cpu was loaded by other stuff, then you would see
biggest GRO packets.

GRO is not : "We want to kill latency and have big packets just because
its better"

Its more like : If load is big enough, try to aggregate TCP frames in
less skbs.