X-Recipient: archive-cygwin AT delorie DOT com DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:subject:to:references:from:message-id:date :mime-version:in-reply-to:content-type :content-transfer-encoding; q=dns; s=default; b=RMXQSjXzOG93GpuI 3hEwrclMqtdM1p4oaizR9w5VHVuIP/se2iNPGG8rl4FyNVpGWSXhdQ7Rd/J9Tcfi XZpXrQntrRiVK0JemCGgIjqFtNZR0FKPvzoV/Rkf/jR5GN4Y2JbXXNdnf5ywi6HJ r1RFPGO6HPyZSX7Y0ZGw5ikSNu4= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:subject:to:references:from:message-id:date :mime-version:in-reply-to:content-type :content-transfer-encoding; s=default; bh=CB9GJRIFWGcSgF4nGASRVe kEujw=; b=dnU1wrsJx60FhnloI1irxGlnR4aimCKN+8EEN+50HmjXJztZmR92yh G1CrBBDj1nFhM0x86akWQ66oDlo7pEHxRUxIzfN+eVX2N11tBgg7RXShDfje2UyB WWzOn3qy6NCqbBQfSweNNCW41DMvnvoPWVvKppejcaQGbSH+rnJLo= Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com Delivered-To: mailing list cygwin AT cygwin DOT com Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.3 required=5.0 tests=AWL,BAYES_00,FREEMAIL_FROM,RCVD_IN_DNSWL_LOW,SPF_PASS autolearn=ham version=3.3.2 spammy=Hx-languages-length:1903, gregfreemyergmailcom, greg DOT freemyer AT gmail DOT com, H*i:sk:O7y-6YE X-HELO: mail-wm0-f45.google.com X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding; bh=5M3WVQ3GdLUSlh7qGs7sq9hXNDfVUDZarewohUuXav4=; b=FfcgoT94Vk47SHhsy14KVqqbdnkwTXTTCIlM0J9IrRucIR2JxnTb94TZ09048kvzE5 bi23BbiKFsckZe5YKi/2AiBbwTwZcvugawFO9GBLg8g06TfQs5LECISYOiCViSE9AMeX +X9lz7SbooX14WSN5mEcCg4CzMGum0gvgTSUm68DgqdsJhCl/eLuL0fLmS+95ah+J1qI 3XER8SVbwO0AXkUHaQP5PVnXVupBV8qtxqEHvU+WF99dlUS8+ObboQ+DcG8Piy/3tjUT 0H6b8CTVgxLsCtD1JMPg0SqFyXixhRgWkf7ThNbanv+x+x248R8l9kdXrT9mbRPimAy+ mZmA== X-Gm-Message-State: AD7BkJLt2Y/9d7+YSmaDRuIyRJcGo73aR6mVfqEh1ix9jpFA8rESLs9IpxOWspOZ7ZEixA== X-Received: by 10.28.175.201 with SMTP id y192mr20449023wme.54.1460396096215; Mon, 11 Apr 2016 10:34:56 -0700 (PDT) Subject: Re: rsync performance degradation? Could be a windows issue? To: cygwin AT cygwin DOT com References: From: Marco Atzeri Message-ID: <570BE03D.7030709@gmail.com> Date: Mon, 11 Apr 2016 19:34:53 +0200 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.7.2 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes On 11/04/2016 18:57, Greg Freemyer wrote: > On Thu, Mar 31, 2016 at 4:48 PM, Greg Freemyer wrote: >> All, >> >> I'm not sure this is on-topic, but at least I'm in cygwin when I >> notice the below: >> >> I do a lot of large data transfers between USB drives. Often I get >> great speeds (70MB/sec or more). >> >> Sometimes it falls way off to closer to 20MB/sec with the same class >> of hardware. >> >> I experienced the "slow" transfer speed today, so I thought I'd ask if >> anyone knew a way to resolve it? > > I'm trying rsync of a bunch of large files again today. > > Initially I saw the same slow copy speed (about 20 MB/sec). My > destination was connected to a USB 3.1 port, but it seemed to be the > bottleneck so I moved it to a USB 3 port (3.1 should be 2x the speed > of 3.0, so it should not have been the bottleneck). > > After getting my throughput up above 50 MB/sec I notice in the windows > "performance monitor" that my source disk is hitting 100% utilization, > then a few seconds later my destination disk is. And back and forth. > It seems I'm only reading or writing for a few seconds, then > alternating. > > I assume the issue is that too much data is being read / cached by > rsync prior to it being written out so I'm getting no advantage of > reading and writing in parallel. > > (I gather iostat isn't available for cygwin?) > > Is there some rsync (or cygwin) option / feature that would encourage > parallel reading/writing? > > fyi: I did some linux testing with "dd" over the weekend and I hit 140 > MB/sec if I used a 100MB blocksize. That was to / from the raw disk > (/dev/sda => /dev/sdb). > > If I bumped my blocksize to 1GB for dd in linux, my throughput dropped > to 70 MB/sec just as I see right now with rsync in cygwin. > > Thanks > Greg > Is windows robocopy faster ? -- 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