From owner-freebsd-net@freebsd.org Sat Feb 2 23:42:27 2019 Return-Path: Delivered-To: freebsd-net@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 9471F14D3AE4 for ; Sat, 2 Feb 2019 23:42:27 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mailman.ysv.freebsd.org (mailman.ysv.freebsd.org [IPv6:2001:1900:2254:206a::50:5]) by mx1.freebsd.org (Postfix) with ESMTP id 2467A6F991 for ; Sat, 2 Feb 2019 23:42:27 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: by mailman.ysv.freebsd.org (Postfix) id D98CF14D3AE3; Sat, 2 Feb 2019 23:42:26 +0000 (UTC) Delivered-To: net@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 9C30E14D3AE2 for ; Sat, 2 Feb 2019 23:42:26 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.ysv.freebsd.org (mxrelay.ysv.freebsd.org [IPv6:2001:1900:2254:206a::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.ysv.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 3840A6F98C for ; Sat, 2 Feb 2019 23:42:26 +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 mxrelay.ysv.freebsd.org (Postfix) with ESMTPS id 545C6D7D7 for ; Sat, 2 Feb 2019 23:42:25 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id x12NgPMA045239 for ; Sat, 2 Feb 2019 23:42:25 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id x12NgPoO045238 for net@FreeBSD.org; Sat, 2 Feb 2019 23:42:25 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: net@FreeBSD.org Subject: [Bug 235031] [em] em0: poor NFS performance, strange behavior Date: Sat, 02 Feb 2019 23:42:25 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: 12.0-RELEASE X-Bugzilla-Keywords: IntelNetworking, regression X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: rmacklem@FreeBSD.org X-Bugzilla-Status: Open X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: net@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: cc Message-ID: In-Reply-To: References: 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-net@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 02 Feb 2019 23:42:27 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D235031 Rick Macklem changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |rmacklem@FreeBSD.org --- Comment #27 from Rick Macklem --- A little off topic, but rsize,wsize will be set to a power of 2 at or below the argument. As such, rsize=3D10240,wsize=3D10240 will result in a setting of 8K (or less if the server forces it) for both of them. You can use "nfsstat -m" on the client to see what is actually being used. I can't help much, but I would suggest trying increasing powers of 2 for rsize,wsize until performance tanks. A couple of reasons smaller rsize,wsize might perform better. - TSO is broken. This can be tested by using the sysctl to disable TSO. (I suggest the generic sysctl and not a driver specific ifconfig, in case the driver config flag is broken.) - Small send or receive rings that can't handle the burst of packets/mbufs that the larger I/O size causes. A write request/receive reply will typically be a chain of size/2K + 2 mb= ufs for the sender. (Sometimes +3 depending on how the driver handles the MAC header.) The receiver will typically see this as a burst of roughly size/1500 + 1 packets making up one TCP segment. If jumbo packets are in use, all bets are off for the receive side, since at least the >4K ones can fragment the mbuf cluster pool. - Interrupt throttling. Since most NFS RPCs are small messages requiring a small reply message in the opposite direction, anything that increases latency (such as delaying interrupts assuming more packets of a stream will arrive soon) can hit NFS performance. --=20 You are receiving this mail because: You are the assignee for the bug.=