tcp tuning tcp_abort_on_overflow

$cat /proc/sys/net/ipv4/tcp_abort_on_overflow
0
$
The tcp_abort_on_overflow variable tells the kernel to reset new connections if the system is currently overflowed with new connection attempts that the daemon(s) can not handle. What this means, is that if the system is overflowed with 1000 large requests in a burst, connections may be reset since we can not handle them if this variable is turned on. If it is not set, the system will try to recover and handle all requests.

This variable takes an boolean value (ie, 1 or 0) and is per default set to 0 or FALSE. Avoid enabling this option except as a last resort since it most definitely harm your clients. Before considering using this variable you should try to tune up your daemons to accept connections faster.

Copyright © 2002 by Oskar Andreasson Under GNU FDL.

 code snippet from linux kernel source  sysctl_net_ipv4.c

                .ctl_name       = NET_TCP_ABORT_ON_OVERFLOW,
                .procname       = "tcp_abort_on_overflow",
                .data           = &sysctl_tcp_abort_on_overflow,
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec

 code snippet from linux kernel source  tcp_minisocks.c

listen_overflow:
        if (!sysctl_tcp_abort_on_overflow) {
                inet_rsk(req)->acked = 1;
                return NULL;
        }