Rajagopal Kunhappan writes: > > > Roch - PAE wrote: > > Sebastien Roy writes: > > > Rajagopal Kunhappan wrote: > > > > The tuning that you have done is rather weird. By default, > > > > ip_squeues_per_cpu has a value of 1. But that does not mean that only > > > > one squeue will be there for a CPU. More squeues upto a maximum of 32 > > > > can get allocated for a CPU and they get allocated on demand. So > > setting > > > > ip_squeues_per_cpu to 32 is not very interesting. > > > > > > > > What is interesting is that you have set ip_soft_rings_cnt to 2 > > times > > > > ip_squeues_per_cpu which would be 64 in your case. This does not seem > > > > right. > > > > > > > > If you have a 64 CPU system and want to use all of them to process > > > > incoming packets for a NIC, then it may just be ok, but having more > > soft > > > > rings than the number of CPUs does not give you any performance > > advantage. > > > > > > > > My suggestion is to not change ip_squeues_per_cpu at all but tune > > > > ip_soft_rings_cnt only. Set it to 2 or 3 for 1Gbps NIC and anywhere > > from > > > > 16 to 32 for 10 Gbps NIC. Again don't increase the soft ring count to > > > > more than the number of CPUs in the system. Also note that CPU speed > > is > > > > also important in the calculation. A simple rule of thumb is that a > > 1Ghz > > > > CPU should be able to handle a 1Gbps NIC. > > > > > > Could all of this manual tuning be made obsolete by some simple > > > heuristics in the code which could automatically set these things? The > > > number of CPUs on the system is no secret to the kernel. Will any of > > > the ongoing projects (such as Crossbow or PEF) make this situation > > better? > > > > > > > For now, I don't understand why fanout is not happening. The > > connections are not established in one swoop and so the flow > > should spread to multiple squeues (ip_squeues_fanout=1). Why > > is this not happening ? > > > > ip_squeue_fanout knob was not set initially and it is not a Niagara > system (so fanout is not default). This is my reading. > > -krgopi >
So you agree that setting this flag should be sufficient to spread the load. Shouldn't that flag default to on ? -r > > > > -r > > > > > > > -Seb > > > _______________________________________________ > > > networking-discuss mailing list > > > [email protected] > > > > _______________________________________________ > > networking-discuss mailing list > > [email protected] > > > _______________________________________________ > networking-discuss mailing list > [email protected] _______________________________________________ networking-discuss mailing list [email protected]
