From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 95931 invoked by alias); 25 Mar 2018 00:04:07 -0000 Mailing-List: contact cygwin-help@cygwin.com; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner@cygwin.com Mail-Followup-To: cygwin@cygwin.com Received: (qmail 95571 invoked by uid 89); 25 Mar 2018 00:04:06 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-6.9 required=5.0 tests=BAYES_00,GIT_PATCH_2,T_RP_MATCHES_RCVD autolearn=ham version=3.3.2 spammy=transferring, cygwins, cygwin's, jun X-HELO: Ishtar.sc.tlinx.org Received: from ishtar.tlinx.org (HELO Ishtar.sc.tlinx.org) (173.164.175.65) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Sun, 25 Mar 2018 00:04:05 +0000 Received: from [192.168.3.12] (Athenae [192.168.3.12]) by Ishtar.sc.tlinx.org (8.14.7/8.14.4/SuSE Linux 0.8) with ESMTP id w2P041OE070270; Sat, 24 Mar 2018 17:04:03 -0700 Message-ID: <5AB6E770.8020603@tlinx.org> Date: Sun, 25 Mar 2018 10:24:00 -0000 From: L A Walsh User-Agent: Thunderbird MIME-Version: 1.0 To: cygwin@cygwin.com CC: jgeoghegan60@gmail.com Subject: Re: Network Performance? References: <5AB5825C.8060309@tlinx.org> In-Reply-To: <5AB5825C.8060309@tlinx.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes X-SW-Source: 2018-03/txt/msg00404.txt.bz2 L A Walsh wrote: > Jordan Geoghegan wrote: >> Has anyone ever successfully transferred 150Mbps or more over the >> network using scp/sftp/rsync etc on Cygwin? > ---- What is more important? testing cygwin's scp/sftp/rsync, or using 'ssh' or running under cygwin, or transferring the file to a local backup server from a windows client as fast as possible? Some test notes below(been benching my win<->server speeds since Win98 days)... > Using bs=16.0M, count=64, iosize=1.0G > R:1073741824 bytes (1.0GB) copied, 1.66724 s, 614MB/s > W:1073741824 bytes (1.0GB) copied, 3.48363 s, 294MB/s --- Some additional notes..."/h" is my home directory on the linux server, so 'bin/iotest is a script in my linux home dir. The speeds / values using 'Bytes', (2**3) use the base2 prefixes for consistency. To get values in mbits, multiple by 8.388608. The above test only tests transfer speed -- not file i/o -- it uses /dev/zero for a source and /dev/null for a target. To simplify testing, I created devices 'zero' and 'null' in my home directory: (on linux): > ll zero null crwxrw-rw- 1 1, 3 May 20 2016 null crw-rw-rw- 1 1, 5 Jun 15 2015 zero (on cygwin): /h> ll zero null -rwxrw-rw- 1 0 May 20 2016 null* -rw-rw-rw- 1 0 Jun 15 2015 zero For write, I used cygwin's 'dd' with if=/dev/zero and of=/h/null. For read, I used if=/h/zero and of=/dev/null. Flags for reading: iflag=fullblock conv=nocreat and for writing: oflag=direct iflag=fullblock conv=nocreat,notrunc To test the cpu-bounding, I just tried limiting the clock speeds on the client and server. Limiting the linux-server's max cpu-speed had the most affect on performance: (limited to 1.6GHz instead of 2.4GHz) (33% limitation) Using bs=16.0M, count=256, iosize=4.0G (~35% slowdown) R:4294967296 bytes (4.0GB) copied, 10.4467 s, 392MB/s W:4294967296 bytes (4.0GB) copied, 21.5026 s, 190MB/s Limiting the client (cygwin-win7sp1x64): (~7-13% slowdown) (clock limited to 1.16GHz instead of 3.2) Using bs=16.0M, count=256, iosize=4.0G R:4294967296 bytes (4.0GB) copied, 7.14355 s, 573MB/s W:4294967296 bytes (4.0GB) copied, 15.9781 s, 256MB/s This would indicate that even in the unencrypted case network transfer speed is cpu bound (and this is using Jumbo packets). -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple