diff --git a/include/net/tcp.h b/include/net/tcp.h index a2e323c54457..f730935b824a 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -564,7 +564,6 @@ static __inline__ int tcp_sk_listen_hashfn(struct sock *sk) #define TCP_NAGLE_PUSH 4 /* Cork is overriden for already queued data */ /* sysctl variables for tcp */ -extern int sysctl_max_syn_backlog; extern int sysctl_tcp_timestamps; extern int sysctl_tcp_window_scaling; extern int sysctl_tcp_sack; diff --git a/net/core/request_sock.c b/net/core/request_sock.c index 78fd60a46bf2..bb55675f0685 100644 --- a/net/core/request_sock.c +++ b/net/core/request_sock.c @@ -18,6 +18,22 @@ #include +/* + * Maximum number of SYN_RECV sockets in queue per LISTEN socket. + * One SYN_RECV socket costs about 80bytes on a 32bit machine. + * It would be better to replace it with a global counter for all sockets + * but then some measure against one socket starving all other sockets + * would be needed. + * + * It was 128 by default. Experiments with real servers show, that + * it is absolutely not enough even at 100conn/sec. 256 cures most + * of problems. This value is adjusted to 128 for very small machines + * (<=32Mb of memory) and to 1024 on normal or better ones (>=256Mb). + * Further increasing requires to change hash table size. + */ +int sysctl_max_syn_backlog = 256; +EXPORT_SYMBOL(sysctl_max_syn_backlog); + int reqsk_queue_alloc(struct request_sock_queue *queue, const int nr_table_entries) { diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 485ca9cb1707..2d41d5d6ad19 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1366,21 +1366,6 @@ static inline struct ip_options *tcp_v4_save_options(struct sock *sk, return dopt; } -/* - * Maximum number of SYN_RECV sockets in queue per LISTEN socket. - * One SYN_RECV socket costs about 80bytes on a 32bit machine. - * It would be better to replace it with a global counter for all sockets - * but then some measure against one socket starving all other sockets - * would be needed. - * - * It was 128 by default. Experiments with real servers show, that - * it is absolutely not enough even at 100conn/sec. 256 cures most - * of problems. This value is adjusted to 128 for very small machines - * (<=32Mb of memory) and to 1024 on normal or better ones (>=256Mb). - * Further increasing requires to change hash table size. - */ -int sysctl_max_syn_backlog = 256; - struct request_sock_ops tcp_request_sock_ops = { .family = PF_INET, .obj_size = sizeof(struct tcp_request_sock), @@ -2662,7 +2647,6 @@ EXPORT_SYMBOL(tcp_proc_register); EXPORT_SYMBOL(tcp_proc_unregister); #endif EXPORT_SYMBOL(sysctl_local_port_range); -EXPORT_SYMBOL(sysctl_max_syn_backlog); EXPORT_SYMBOL(sysctl_tcp_low_latency); EXPORT_SYMBOL(sysctl_tcp_tw_reuse);