From 26acc98c1d408fd7878e5399b58433d094b24758 Mon Sep 17 00:00:00 2001 From: andre Date: Wed, 18 Aug 2010 18:05:54 +0000 Subject: If a TCP connection has been idle for one retransmit timeout or more it must reset its congestion window back to the initial window. RFC3390 has increased the initial window from 1 segment to up to 4 segments. The initial window increase of RFC3390 wasn't reflected into the restart window which remained at its original defaults of 4 segments for local and 1 segment for all other connections. Both values are controllable through sysctl net.inet.tcp.local_slowstart_flightsize and net.inet.tcp.slowstart_flightsize. The increase helps TCP's slow start algorithm to open up the congestion window much faster. Reviewed by: lstewart MFC after: 1 week --- sys/netinet/tcp_var.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'sys/netinet/tcp_var.h') diff --git a/sys/netinet/tcp_var.h b/sys/netinet/tcp_var.h index 7482277..b753e10 100644 --- a/sys/netinet/tcp_var.h +++ b/sys/netinet/tcp_var.h @@ -565,6 +565,7 @@ extern int tcp_log_in_vain; VNET_DECLARE(int, tcp_mssdflt); /* XXX */ VNET_DECLARE(int, tcp_minmss); VNET_DECLARE(int, tcp_delack_enabled); +VNET_DECLARE(int, tcp_do_rfc3390); VNET_DECLARE(int, tcp_do_newreno); VNET_DECLARE(int, path_mtu_discovery); VNET_DECLARE(int, ss_fltsz); @@ -575,6 +576,7 @@ VNET_DECLARE(int, ss_fltsz_local); #define V_tcp_mssdflt VNET(tcp_mssdflt) #define V_tcp_minmss VNET(tcp_minmss) #define V_tcp_delack_enabled VNET(tcp_delack_enabled) +#define V_tcp_do_rfc3390 VNET(tcp_do_rfc3390) #define V_tcp_do_newreno VNET(tcp_do_newreno) #define V_path_mtu_discovery VNET(path_mtu_discovery) #define V_ss_fltsz VNET(ss_fltsz) -- cgit v1.1