I have supermicro server with :
* Intel® 7500 (Boxboro-EX) chipset
4 processors with 6 cores in each (Intel(R) Xeon(R) CPU X7542 @ 2.67GHz)
I installed 2 10G intel NICs(82599EB) and the latest ixgbe driver (v3.2.10).
Yesterday I made a test with pktgen and got some strange results(I generated traffic on server (A) and flooded it through supermicro(B)):
1) While I spread interrupts on B 10G nic among 12 cores (the 1-st and the 2-d processors) I recieved 100% utilization on all 12 cores at rate 5Gbit/s (~1 mln pps)
2) While I spread interrupts on B 10G nic among 8 cores (the 1-st (6cores) and the 2-d(2cores) processors) I recieved 100% utilization on all 8 cores at rate 7Gbit/s (~1 mln pps)
3) While I spread interrupts on B 10G nic among 6 cores (the 1-st (6cores) processors) I DID NOT recieved 100% utilization and I could forward 9.5Gbit/s (~1 mln pps)
Of course I have heard that spreading interrupts among different processors could make things worth, but not so dramatically.
I made test on 2.6.37-gentoo-r1.
So can you tell me, how to overcome this problem?