From owner-freebsd-bugs@freebsd.org Mon Jul 11 12:37:21 2016 Return-Path: Delivered-To: freebsd-bugs@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 730AEB9166C for ; Mon, 11 Jul 2016 12:37:21 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 498BA1623 for ; Mon, 11 Jul 2016 12:37:21 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from bugs.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id u6BCbLuI022794 for ; Mon, 11 Jul 2016 12:37:21 GMT (envelope-from bugzilla-noreply@freebsd.org) From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 211003] net.inet.tcp.delayed_ack=0 and local TCP traffic Date: Mon, 11 Jul 2016 12:37:21 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: 10.2-STABLE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Many People X-Bugzilla-Who: moko@moko.ru X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: freebsd-bugs@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 11 Jul 2016 12:37:21 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D211003 Bug ID: 211003 Summary: net.inet.tcp.delayed_ack=3D0 and local TCP traffic Product: Base System Version: 10.2-STABLE Hardware: Any OS: Any Status: New Severity: Affects Many People Priority: --- Component: kern Assignee: freebsd-bugs@FreeBSD.org Reporter: moko@moko.ru We have many FreeBSD installations and some of them historically have the following settings in /etc/sysctl.conf: net.inet.tcp.delayed_ack=3D0 net.inet.tcp.recvspace=3D8192 net.inet.tcp.sendspace=3D150000 After upgrading to 10.2 we've run into an issue - local http requests were delaying after every 8kb of data for 5 seconds. lynx --mime_header "http:///any file around 200kb" first we get 4Kb (incuding headers) 5 seconds delay (exact value, not an approximate) next 8Kb 5 seconds delay next 8Kb ... and so on. Everything is fine if the file is requested remotely, only local requests h= ave such delays. Nginx or apache - both have the delays. We also where able to reproduce the delays in virtualized environment. There are no issues with t= his sysctl settings in FreeBSD 8.X and FreeBSD 9.X. Setting net.inet.tcp.sendspace=3D4096 "hides" the issue. Increasing net.inet.tcp.recvspace to more then 32664 also "hides" the issue. Restoring net.inet.tcp.delayed_ack to default 1 also "hides" the issue but there are still some performance issues if net.inet.tcp.recvspace is low: >sysctl net.inet.tcp.recvspace=3D8192 >time lynx --mime_header "local file around 200 kb" > /dev/null 0.009u 0.000s 0:01.41 0.0% 0+0k 0+0io 0pf+0w >sysctl net.inet.tcp.recvspace=3D32768 >time lynx --mime_header "local file around 200 kb" > /dev/null 0.009u 0.000s 0:00.01 0.0% 0+0k 0+0io 0pf+0w --=20 You are receiving this mail because: You are the assignee for the bug.=