From owner-freebsd-fs@freebsd.org Sun Aug 14 20:21:52 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 88A48BBAFCA for ; Sun, 14 Aug 2016 20:21:52 +0000 (UTC) (envelope-from ben.rubson@gmail.com) Received: from mail-wm0-x241.google.com (mail-wm0-x241.google.com [IPv6:2a00:1450:400c:c09::241]) (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 1BFEB12F0 for ; Sun, 14 Aug 2016 20:21:52 +0000 (UTC) (envelope-from ben.rubson@gmail.com) Received: by mail-wm0-x241.google.com with SMTP id o80so7898744wme.0 for ; Sun, 14 Aug 2016 13:21:52 -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=5R6cu/LHZsRzYjaOMPwyV7bv6xVtn+EQldW/WrjO9vk=; b=dT2l8/2YJBu0B63ZdHdXf8jzTF442PZMPuZpAg2v6gj9Bx1/4TEjhrbk5krXa8hHcn ULCaieAX9zSnKn+CT9FNu2TWQz6mvIwLLChMFK3IlLBLlHeLLlV34WXyB0jluZS4yi6N VrHFOa00HzU6npFZ/g24rHJ1lIlAXx7J6K8TGpI9RDDxGyEdVuhQFHoZGTtBSRPrZiZM YIO21NmbIw8GRT8gNUnj+NxgLNZ7WOsBsaXPF4K9qI1s/RNNTEwPCHHt3Li6o/X94oRQ mhH8RQny6Jdy1tC22SZdMIbPSlRKdlJ1HjGcxsSkfDKLfsnxASnnlxgfJWV2ITsEybx/ HoZw== 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=5R6cu/LHZsRzYjaOMPwyV7bv6xVtn+EQldW/WrjO9vk=; b=D9AbMtvcuxienCGuIK4GbzWOTTRSt51dn5XoN6GxM5dqrnZcMseIAXOXi1jF/6W1zU yr/3fNgqHND/qV9cwRtN22PCd1wc6xfKIssgopDEPBCDVlAhe58mH4pS/lcOfyEUbATl DiAzQhp01G3pSlUPP50zHkDM7Ggpv8SzUZFgBCZndlRPHnlixcRAwXfjjHbwjocdfNVR tzHyCa9Y9J1/CbJSMIRqklkPupMetV0bPWWVxdua0WLiHUC+GuCxzWM0BVuvRJobovil 3G9YvAbwG9BfyPuXVm2TkK2agaf99URu27VLlnx3BdA6u+xLL+nHB207duXExyiKraIo c5Sw== X-Gm-Message-State: AEkoouuIegt27R4DI13nlofqi5fIwjge/ixhreFWms/jUZyLJnbMVIvHHnQhi1R18/LjwQ== X-Received: by 10.194.184.148 with SMTP id eu20mr26620245wjc.137.1471206110284; Sun, 14 Aug 2016 13:21:50 -0700 (PDT) Received: from macbook-air-de-benjamin.home (LFbn-1-7077-85.w90-116.abo.wanadoo.fr. [90.116.246.85]) by smtp.gmail.com with ESMTPSA id r67sm13134423wmb.14.2016.08.14.13.21.49 for (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Sun, 14 Aug 2016 13:21:49 -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: <7CE3E62B-8251-4390-BD90-CF2F76F57CA7@gmail.com> Date: Sun, 14 Aug 2016 22:21:48 +0200 Content-Transfer-Encoding: quoted-printable Message-Id: References: <6B32251D-49B4-4E61-A5E8-08013B15C82B@gmail.com> <20160810114404.GA80485@brick> <7CE3E62B-8251-4390-BD90-CF2F76F57CA7@gmail.com> 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: Sun, 14 Aug 2016 20:21:52 -0000 > On 10 Aug 2016, at 15:27, Ben RUBSON wrote: >=20 >>=20 >> 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$((128*1024)) count=3D81920 >>> 10737418240 bytes transferred in 34.731815 secs (309152234 = bytes/sec) - 295MB/s >>>=20 >>> With 2 parallel dd jobs : 345MB/s >>> With 4 parallel dd jobs : 502MB/s >>>=20 >>>=20 >>>=20 >>> ### Questions : >>>=20 >>> Why such a difference ? >>> Where are the 167MB/s (462-295) lost ? >>=20 >> Network delays, I suppose. >=20 > I just saw that iSER is available in FreeBSD 11, let's install BETA4 = and give it a try. OK, as a target I used Linux TGT, as iSER target (isert) is not FreeBSD = available yet. ### Target : local disk throughput, one thread : # dd if=3D/dev/da8 of=3D/dev/null bs=3D$((128*1024)) count=3D81920 10737418240 bytes (11 GB) copied, 21.3898 s, 502 MB/s ### Initiator : iscsi disk throughput, one thread : # dd if=3D/dev/da8 of=3D/dev/null bs=3D$((128*1024)) count=3D81920 10737418240 bytes transferred in 34.938676 secs (307321843 bytes/sec) - = 293 MB/s ### Initiator : iSER disk throughput, one thread : # dd if=3D/dev/da8 of=3D/dev/null bs=3D$((128*1024)) count=3D81920 10737418240 bytes transferred in 20.371947 secs (527068838 bytes/sec) - = 502 MB/s No need to comment, let's wait for the FreeBSD iSER target then ! Ben