• Eric Dumazet's avatar
    net: sk_add_backlog() take rmem_alloc into account · c377411f
    Eric Dumazet authored
    Current socket backlog limit is not enough to really stop DDOS attacks,
    because user thread spend many time to process a full backlog each
    round, and user might crazy spin on socket lock.
    We should add backlog size and receive_queue size (aka rmem_alloc) to
    pace writers, and let user run without being slow down too much.
    Introduce a sk_rcvqueues_full() helper, to avoid taking socket lock in
    stress situations.
    Under huge stress from a multiqueue/RPS enabled NIC, a single flow udp
    receiver can now process ~200.000 pps (instead of ~100 pps before the
    patch) on a 8 core machine.
    Signed-off-by: default avatarEric Dumazet <eric.dumazet@gmail.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
sock.h 48.8 KB