I have been getting these UDP
floods with random IPs and ports.
randomip:randomport -> myip:randomport
0 byte payload
For some reason it is using a lot of CPU. Here is the results of perf top -e cycles:k
.
Is there any way to optimize the kernel?
10.42% [kernel] [k] inet_getpeer
7.59% [kernel] [k] inet_getpeer.part.4
6.15% [kernel] [k] peer_avl_rebalance.isra.2
3.38% [kernel] [k] fib_table_lookup
2.77% [ip_tables] [k] ipt_do_table
1.98% [e1000e] [k] e1000_clean_rx_irq
1.82% [kernel] [k] md5_transform
1.69% [kernel] [k] __ip_route_output_key
1.36% [kernel] [k] check_leaf.isra.7
1.34% [kernel] [k] __udp4_lib_lookup
1.31% [kernel] [k] kmem_cache_free
1.09% [kernel] [k] __netif_receive_skb_core
1.01% [kernel] [k] __slab_free
1.00% [kernel] [k] __ip_append_data.isra.38
0.99% [kernel] [k] memcpy
0.98% [kernel] [k] kmem_cache_alloc
0.91% [kernel] [k] icmp_send
0.89% [xt_multiport] [k] multiport_mt
0.83% [kernel] [k] update_blocked_averages
0.79% [kernel] [k] kfree
0.79% [kernel] [k] __switch_to
0.78% [kernel] [k] skb_release_data
0.72% [kernel] [k] csum_partial_copy_generic
0.71% [kernel] [k] _raw_spin_lock_irqsave
0.67% [kernel] [k] ip_route_input_noref
0.63% [kernel] [k] __udp4_lib_rcv
0.61% [kernel] [k] dev_gro_receive
0.59% [kernel] [k] __schedule
0.59% [kernel] [k] __ip_make_skb
0.57% [kernel] [k] __copy_skb_header
0.56% [kernel] [k] sock_alloc_send_pskb
0.55% [kernel] [k] nf_iterate