From mboxrd@z Thu Jan 1 00:00:00 1970 From: Fan Du Subject: [PATCHv5 net-next 1/4] ipv4: Raise tcp PMTU probe mss base size Date: Fri, 6 Mar 2015 11:18:22 +0800 Message-ID: <1425611905-28503-2-git-send-email-fan.du@intel.com> References: <1425611905-28503-1-git-send-email-fan.du@intel.com> Cc: davem@davemloft.net, edumazet@google.com, netdev@vger.kernel.org, fengyuleidian0615@gmail.com To: jheffner@psc.edu Return-path: Received: from mga03.intel.com ([134.134.136.65]:38531 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754121AbbCFDXT (ORCPT ); Thu, 5 Mar 2015 22:23:19 -0500 In-Reply-To: <1425611905-28503-1-git-send-email-fan.du@intel.com> Sender: netdev-owner@vger.kernel.org List-ID: Quotes from RFC4821 7.2. Selecting Initial Values It is RECOMMENDED that search_low be initially set to an MTU size that is likely to work over a very wide range of environments. Given today's technologies, a value of 1024 bytes is probably safe enough. The initial value for search_low SHOULD be configurable. Moreover, set a small value will introduce extra time for the search to converge. So set the initial probe base mss size to 1024 Bytes. Signed-off-by: Fan Du Acked-by: John Heffner --- include/net/tcp.h | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index 8d6b983..7b57e5b 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -65,7 +65,7 @@ void tcp_time_wait(struct sock *sk, int state, int timeo); #define TCP_MIN_MSS 88U /* The least MTU to use for probing */ -#define TCP_BASE_MSS 512 +#define TCP_BASE_MSS 1024 /* After receiving this amount of duplicate ACKs fast retransmit starts. */ #define TCP_FASTRETRANS_THRESH 3 -- 1.7.1