From owner-freebsd-fs@freebsd.org Wed Aug 10 13:27:19 2016 Return-Path: Delivered-To: freebsd-fs@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 26995BB4D57 for ; Wed, 10 Aug 2016 13:27:19 +0000 (UTC) (envelope-from ben.rubson@gmail.com) Received: from mail-wm0-x242.google.com (mail-wm0-x242.google.com [IPv6:2a00:1450:400c:c09::242]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id AF3411752 for ; Wed, 10 Aug 2016 13:27:18 +0000 (UTC) (envelope-from ben.rubson@gmail.com) Received: by mail-wm0-x242.google.com with SMTP id o80so9543096wme.0 for ; Wed, 10 Aug 2016 06:27:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:subject:from:in-reply-to:date :content-transfer-encoding:message-id:references:to; bh=D2KVe/wbULAQMNJwit67vtxA3SAX6hCc5yUlSn7M6+o=; b=w8wc8o4ehyRjFc54zJ5yEo+K6BI5kpb8LoRri2o5ALjpZwcZIVVyIclZF0xj4Z9rHp 5jgY9k7qKj4+BHA5DAgPZ/fDpjJ7gKOj1D3Jva/nfUWSNDWtb88TZDhBqXAFhNZHNlY4 XcKS2nCbANF9mVsrXnmrR/8Ao+8hcDXh/mwnArCscyBqxZ/Ty7Zjp9qqx05guE80PpYM 0qtSA5/P2gNuruxhgkHZgaYNmrYI1Cts0jq11/OTPjtidsVwwalvDTw/HiO6jcx5ZGNH d3hQqaKN9dR6O6AU/GlpdAjPnlTHwCHaMG9FhPUEGWUyNNVa36bD6irGWRX/61JGsZB7 uPTQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:subject:from:in-reply-to:date :content-transfer-encoding:message-id:references:to; bh=D2KVe/wbULAQMNJwit67vtxA3SAX6hCc5yUlSn7M6+o=; b=aH3kYruuS4a6HD+ndnXcgOkvfKnHVuVWvnxjrERNaWt33KdLtFlDytsF2RCIRYspUJ yDIvBHF+hsPtn8iVlMs03znvYHiv1ymFhGKkbsOwO8s9/SQ46J4WNdrR2K3aCDWDaSXW X99yVleBD11dFcfhOSyCHMv5XF2gWX55AXdhV4zNBL4TCfGZsLYivRFeyBbv7yiiXhgo 5wiwlFQcGNubcd8wXRQsDqosotVtpRZ8RusUh150UGLjVONryITFjJsAdETj3JI+bxLH EIKDLAHNb7QmG4SU1I9jaUD031lFMh2R9Jl8gYFXuLdZmtMRHwAKGmWoqh2hgZjyoxhr viNA== X-Gm-Message-State: AEkoousu9sCJGFoWakEKpr+t+/ZLqQ5jqK4V4o0Lvn2tNpRYYS70RcD4Yv7uJJ3rcoTOkQ== X-Received: by 10.194.148.81 with SMTP id tq17mr3946188wjb.67.1470835636828; Wed, 10 Aug 2016 06:27:16 -0700 (PDT) Received: from macbook-air-de-benjamin-1.home (LFbn-1-7077-85.w90-116.abo.wanadoo.fr. [90.116.246.85]) by smtp.gmail.com with ESMTPSA id o4sm43055788wjd.15.2016.08.10.06.27.16 for (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 10 Aug 2016 06:27:16 -0700 (PDT) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 9.3 \(3124\)) Subject: Re: [iSCSI] Trying to reach max disk throughput From: Ben RUBSON In-Reply-To: <20160810114404.GA80485@brick> Date: Wed, 10 Aug 2016 15:27:15 +0200 Content-Transfer-Encoding: quoted-printable Message-Id: <7CE3E62B-8251-4390-BD90-CF2F76F57CA7@gmail.com> References: <6B32251D-49B4-4E61-A5E8-08013B15C82B@gmail.com> <20160810114404.GA80485@brick> To: freebsd-fs@freebsd.org X-Mailer: Apple Mail (2.3124) X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 10 Aug 2016 13:27:19 -0000 > On 10 Aug 2016, at 13:44, Edward Tomasz Napiera=C5=82a = wrote: >=20 > On 0810T1154, Ben RUBSON wrote: >> Hello, >>=20 >> I'm facing something strange with iSCSI, I can't manage to reach the = expected disk throughput using one (read or write) thread. >=20 > [..] >=20 >> ### Initiator : iscsi disk throughput : >>=20 >> ## dd if=3D/dev/da8 of=3D/dev/null bs=3D$((128*1024)) count=3D81920 >> 10737418240 bytes transferred in 34.731815 secs (309152234 bytes/sec) = - 295MB/s >>=20 >> With 2 parallel dd jobs : 345MB/s >> With 4 parallel dd jobs : 502MB/s >>=20 >>=20 >>=20 >> ### Questions : >>=20 >> Why such a difference ? >> Where are the 167MB/s (462-295) lost ? >=20 > Network delays, I suppose. I just saw that iSER is available in FreeBSD 11, let's install BETA4 and = give it a try.=