• subashab@codeaurora.org's avatar
    net: Add sysctl to toggle early demux for tcp and udp · dddb64bc
    subashab@codeaurora.org authored
    Certain system process significant unconnected UDP workload.
    It would be preferrable to disable UDP early demux for those systems
    and enable it for TCP only.
    
    By disabling UDP demux, we see these slight gains on an ARM64 system-
    782 -> 788Mbps unconnected single stream UDPv4
    633 -> 654Mbps unconnected UDPv4 different sources
    
    The performance impact can change based on CPU architecure and cache
    sizes. There will not much difference seen if entire UDP hash table
    is in cache.
    
    Both sysctls are enabled by default to preserve existing behavior.
    
    v1->v2: Change function pointer instead of adding conditional as
    suggested by Stephen.
    
    v2->v3: Read once in callers to avoid issues due to compiler
    optimizations. Also update commit message with the tests.
    
    v3->v4: Store and use read once result instead of querying pointer
    again incorrectly.
    
    v4->v5: Refactor to avoid errors due to compilation with IPV6={m,n}
    Signed-off-by: default avatarSubash Abhinov Kasiviswanathan <subashab@codeaurora.org>
    Suggested-by: default avatarEric Dumazet <edumazet@google.com>
    Cc: Stephen Hemminger <stephen@networkplumber.org>
    Cc: Tom Herbert <tom@herbertland.com>
    Cc: David Miller <davem@davemloft.net>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    dddb64bc
ip6_input.c 10 KB