From owner-freebsd-bugs@FreeBSD.ORG Mon Aug 15 16:40:04 2011 Return-Path: Delivered-To: freebsd-bugs@hub.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id AF2BF106566B for ; Mon, 15 Aug 2011 16:40:04 +0000 (UTC) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (freefall.freebsd.org [IPv6:2001:4f8:fff6::28]) by mx1.freebsd.org (Postfix) with ESMTP id 881388FC1B for ; Mon, 15 Aug 2011 16:40:04 +0000 (UTC) Received: from freefall.freebsd.org (localhost [127.0.0.1]) by freefall.freebsd.org (8.14.4/8.14.4) with ESMTP id p7FGe47M025586 for ; Mon, 15 Aug 2011 16:40:04 GMT (envelope-from gnats@freefall.freebsd.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.14.4/8.14.4/Submit) id p7FGe4jj025585; Mon, 15 Aug 2011 16:40:04 GMT (envelope-from gnats) Resent-Date: Mon, 15 Aug 2011 16:40:04 GMT Resent-Message-Id: <201108151640.p7FGe4jj025585@freefall.freebsd.org> Resent-From: FreeBSD-gnats-submit@FreeBSD.org (GNATS Filer) Resent-To: freebsd-bugs@FreeBSD.org Resent-Reply-To: FreeBSD-gnats-submit@FreeBSD.org, Darren Baginski Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 0FC901065694 for ; Mon, 15 Aug 2011 16:37:21 +0000 (UTC) (envelope-from nobody@FreeBSD.org) Received: from red.freebsd.org (red.freebsd.org [IPv6:2001:4f8:fff6::22]) by mx1.freebsd.org (Postfix) with ESMTP id AFD638FC1E for ; Mon, 15 Aug 2011 16:37:20 +0000 (UTC) Received: from red.freebsd.org (localhost [127.0.0.1]) by red.freebsd.org (8.14.4/8.14.4) with ESMTP id p7FGbKSj073454 for ; Mon, 15 Aug 2011 16:37:20 GMT (envelope-from nobody@red.freebsd.org) Received: (from nobody@localhost) by red.freebsd.org (8.14.4/8.14.4/Submit) id p7FGbKpm073453; Mon, 15 Aug 2011 16:37:20 GMT (envelope-from nobody) Message-Id: <201108151637.p7FGbKpm073453@red.freebsd.org> Date: Mon, 15 Aug 2011 16:37:20 GMT From: Darren Baginski To: freebsd-gnats-submit@FreeBSD.org X-Send-Pr-Version: www-3.1 Cc: Subject: kern/159795: excessive duplicate ACKs and TCP session freezes X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 15 Aug 2011 16:40:04 -0000 >Number: 159795 >Category: kern >Synopsis: excessive duplicate ACKs and TCP session freezes >Confidential: no >Severity: critical >Priority: high >Responsible: freebsd-bugs >State: open >Quarter: >Keywords: >Date-Required: >Class: sw-bug >Submitter-Id: current-users >Arrival-Date: Mon Aug 15 16:40:03 UTC 2011 >Closed-Date: >Last-Modified: >Originator: Darren Baginski >Release: 8.2-RELEASE >Organization: N/A >Environment: FreeBSD downloader1.lab.local 8.2-RELEASE FreeBSD 8.2-RELEASE #0: Tue Mar 15 09:14:03 UTC 2011 root@downloader1.lab.local:/usr/obj/usr/src/sys/GENERIC amd64 >Description: There is excessive duplicate ACKs and session freezes while downloading huge files at speed over http or ftp. tcpdump: 19:17:04.022367 IP 10.178.56.18.19930 > 10.178.132.6.80: Flags [.], ack 27950968, win 16384, options [nop,nop,TS val 977541894 ecr 783406220], length 0 19:17:04.022369 IP 10.178.56.18.19930 > 10.178.132.6.80: Flags [.], ack 27950968, win 16384, options [nop,nop,TS val 977541894 ecr 783406220], length 0 19:17:04.022553 IP 10.178.56.18.19930 > 10.178.132.6.80: Flags [.], ack 27950968, win 16384, options [nop,nop,TS val 977541894 ecr 783406220], length 0 19:17:04.022703 IP 10.178.56.18.19930 > 10.178.132.6.80: Flags [.], ack 27950968, win 16384, options [nop,nop,TS val 977541894 ecr 783406220], length 0 19:17:04.022707 IP 10.178.56.18.19930 > 10.178.132.6.80: Flags [.], ack 27950968, win 16384, options [nop,nop,TS val 977541894 ecr 783406220], length 0 19:17:04.022709 IP 10.178.56.18.19930 > 10.178.132.6.80: Flags [.], ack 27950968, win 16384, options [nop,nop,TS val 977541894 ecr 783406220], length 0 19:17:04.022856 IP 10.178.56.18.19930 > 10.178.132.6.80: Flags [.], ack 27950968, win 16384, options [nop,nop,TS val 977541894 ecr 783406220], length 0 19:17:04.023002 IP 10.178.56.18.19930 > 10.178.132.6.80: Flags [.], ack 27950968, win 16384, options [nop,nop,TS val 977541895 ecr 783406220], length 0 19:17:04.023005 IP 10.178.56.18.19930 > 10.178.132.6.80: Flags [.], ack 27950968, win 16384, options [nop,nop,TS val 977541895 ecr 783406220], length 0 19:17:04.023007 IP 10.178.56.18.19930 > 10.178.132.6.80: Flags [.], ack 27950968, win 16384, options [nop,nop,TS val 977541895 ecr 783406220], length 0 19:17:04.023151 IP 10.178.56.18.19930 > 10.178.132.6.80: Flags [.], ack 27950968, win 16384, options [nop,nop,TS val 977541895 ecr 783406220], length 0 19:17:04.023155 IP 10.178.56.18.19930 > 10.178.132.6.80: Flags [.], ack 27950968, win 16384, options [nop,nop,TS val 977541895 ecr 783406220], length 0 19:17:04.023157 IP 10.178.56.18.19930 > 10.178.132.6.80: Flags [.], ack 27950968, win 16384, options [nop,nop,TS val 977541895 ecr 783406220], length 0 19:17:04.023159 IP 10.178.56.18.19930 > 10.178.132.6.80: Flags [.], ack 27950968, win 16384, options [nop,nop,TS val 977541895 ecr 783406220], length 0 19:17:04.023200 IP 10.178.56.18.19930 > 10.178.132.6.80: Flags [.], ack 27950968, win 16384, options [nop,nop,TS val 977541895 ecr 783406220], length 0 19:17:04.023301 IP 10.178.56.18.19930 > 10.178.132.6.80: Flags [.], ack 27950968, win 16384, options [nop,nop,TS val 977541895 ecr 783406220], length 0 >How-To-Repeat: Setup two boxes, connect the via 1Gbit switch and run sequential wget or fetch tests. Receiving box generates excessive ACKs and in about 40% cases tcp session freezes and then timeouts. >Fix: Unknown, but looks like the was similar report http://lists.freebsd.org/pipermail/freebsd-net/2011-February/027895.html >Release-Note: >Audit-Trail: >Unformatted: