From owner-freebsd-performance@FreeBSD.ORG Fri Mar 28 17:31:55 2008 Return-Path: Delivered-To: performance@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id E8800106564A; Fri, 28 Mar 2008 17:31:55 +0000 (UTC) (envelope-from ap00@mail.ru) Received: from mx0.awanti.com (mx0.awanti.com [91.190.112.18]) by mx1.freebsd.org (Postfix) with ESMTP id A2DE38FC15; Fri, 28 Mar 2008 17:31:55 +0000 (UTC) (envelope-from ap00@mail.ru) Received: by mx0.awanti.com (Postfix, from userid 100) id F1AF74C022; Fri, 28 Mar 2008 20:13:18 +0300 (MSK) X-Spam-Flag: NO X-Spam-Checker-Version: SpamAssassin 3.1.9 on mx0.awanti.com X-Spam-Status: No, score=-2.3 required=6.5 tests=AWL,BAYES_00 autolearn=ham version=3.1.9 Received: from pstation (unknown [10.28.4.14]) by mx0.awanti.com (Postfix) with ESMTP id 467204C019; Fri, 28 Mar 2008 20:13:17 +0300 (MSK) Date: Fri, 28 Mar 2008 20:14:58 +0300 From: Anthony Pankov X-Mailer: The Bat! (v1.51) Personal X-Priority: 3 (Normal) Message-ID: <1333421734.20080328201458@mail.ru> To: freebsd-net@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: performance@freebsd.org Subject: packet delay because of blackhole X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: Anthony Pankov List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 28 Mar 2008 17:31:56 -0000 Just for somebody convince. While analyzing client<->server HTTPS conversation one second delay in packet exchange was discovered (strongly reproducible): Sample: N time 6 0.002303 10.28.4.14 10.28.4.50 SSL Client Hello 7 0.106710 10.28.4.50 10.28.4.14 TCP 443 > 1447 [ACK] Seq=1 Ack=103 Win=65535 Len=0 8 1.045712 10.28.4.50 10.28.4.14 TLSv1 Server Hello, Certificate, Server Hello Done Another sample: 10 0.011722 10.28.4.14 10.28.4.50 TLSv1 Application Data 11 0.115933 10.28.4.50 10.28.4.14 TCP 443 > 1442 [ACK] Seq=839 Ack=519 Win=65466 Len=0 12 1.054037 10.28.4.50 10.28.4.14 TLSv1 Application Data The reason for delay is sysctl tcp.blackhole value grater than 0, much to surprise. So, turning tcp.blackhole to 0 eliminate any delay (strongly reproducible). System: FreeBSD 6_2_stable -- Best regards, Anthony mailto:ap00@mail.ru