From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from nm2-vm5.access.bullet.mail.bf1.yahoo.com (nm2-vm5.access.bullet.mail.bf1.yahoo.com [216.109.114.92]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id D91503B260 for ; Mon, 28 Nov 2016 14:42:13 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rogers.com; s=s2048; t=1480362133; bh=H0P01pXno0k0do/SxFDY7SuwNiZZE3SchZIT/nWv2zE=; h=Reply-To:Subject:References:To:Cc:From:Date:In-Reply-To:From:Subject; b=YCQN/FzYACULXJuvJpmsmZ0WG/0hu6DqxAou27vlF6+r33Pd4tXqCz3thWQklx7oSPf3wp+QQahUZxNEQ65npAnSxzWdxG+mZnB6lnJTURHHXWcK5StHsDawJf2rSJ8vPIQdMG9t4vYoDHqlYK48c1e1DYv+q+G2C5vjRzDbQ28hGPUfJLjQg5XhFMMcgx9WcFapYwXRiaBckv08D0nwduqqo7H+SSwMTvcF20W1CGkJ2DAmhyFtWAM0XU4PsQC7JxAI4svu536trp7C8WGuHekBofqFszGb4DzbUlQHLAPC2MrlrUrNMAO7bGUL/AVCViwdWEvFjJJFDYjQZrje7w== Received: from [66.196.81.165] by nm2.access.bullet.mail.bf1.yahoo.com with NNFMP; 28 Nov 2016 19:42:13 -0000 Received: from [98.139.244.49] by tm11.access.bullet.mail.bf1.yahoo.com with NNFMP; 28 Nov 2016 19:42:13 -0000 Received: from [127.0.0.1] by smtp111.sbc.mail.bf1.yahoo.com with NNFMP; 28 Nov 2016 19:42:13 -0000 X-Yahoo-Newman-Id: 298325.29755.bm@smtp111.sbc.mail.bf1.yahoo.com X-Yahoo-Newman-Property: ymail-3 X-YMail-OSG: MC6hmD8VM1kYcQQ2oBzgDKs0y6xTeSjAJH6pQsu0S3OEIzv OIMbNS3IeAUlTtknPBwf7wPkqVcTDtPLngHyPfTP1_gX1oIOitPIfR5h9BlX mVLx36uDVDDaJ2flPN2iUYoN85IOJQwhCgexVOjelGq2tTC0mMgb4oE5dYi2 i2F731WudJRM_CQGCILcoBMZ_vOg8UCanpzORqQTKGX4NNjKu2F84bGL8ieh VwdayweCr2YVSY2F_96W0Mxocwscqg1L9Gl1NsMr79SzFiLNgUIYWiYH3Fj5 H5QxZX4jqubB8uAJg89HkDX14A4iL.PHMH2hKf1WYksfEyjTldrC1bx2Has4 RU.JxauYSPL7or8yran_VVv5R4lTvKhgDLGAl7Uv5Im9sFfA99WEziYE1Hjw 8wt5hue9PwWytfPmN4haoC0WghGYaoajQ8PRr1Jnk3hsBPQ7xZB1B43ORx1s uaXQRDYu8fpXBa82l1OQUB0QdCvxImHjmbpSNp7pY1pX6NmIea9.0gy73u96 wAPs9rACxLB_wNE7WRuk7RfK_8j2pDI5oztLWRNYL5fZZ.MKMwM20JuisCqH u X-Yahoo-SMTP: sltvjZWswBCRD.ElTuB1l9j6s9wRYPpuyTNWOE5oEg-- Reply-To: davecb@spamcop.net References: <836b6c89-d7a0-49e1-e1b4-8e98b9263c1d@pollere.com> <499965DD-26DF-42A2-B79A-95109C13C950@gmail.com> To: Jonathan Morton , davecb@spamcop.net Cc: bloat@lists.bufferbloat.net From: David Collier-Brown Message-ID: Date: Mon, 28 Nov 2016 14:42:12 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <499965DD-26DF-42A2-B79A-95109C13C950@gmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Subject: Re: [Bloat] How to "sell" improvement X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 28 Nov 2016 19:42:14 -0000 On 28/11/16 02:26 PM, Jonathan Morton wrote: >> On 28 Nov, 2016, at 20:37, David Collier-Brown wrote: >> >> I'm using latency as the time from the request to the first response >> transfer time as the time from the first response to the last response, which may be 0, and >> >> sleep/think time as the time from the last response to the next request, for a given stream of requests and responses, AKA "transactions" > This is a useful set of definitions, though I would quibble that “transfer time” should also be measured from the request, not from the first response. Latency + Transfer Time add up to make "Response Time", which is from very beginning to very end, as you note. > > A more complete picture would add a measure of application-induced delay, which is visible to the user but not necessarily to the network. It is influenced mainly by the end host's performance, not by anything in the network, and would presumably count as part of the “think time” for many applications. Hence it’s not relevant for *our* objectives, but might be to others. The response also breaks down into queue delay and service time, which don't line up with the latency/transfer split. Service time is the time a warm system takes to process one request-response pair, while delay is the time spent waiting for the cache to load, stuff get read from disk and, especially especially, the time sitting in the run-queue, twiddling your thumbs, waiting for a CPU. Those aren't easily measured from outside the system, although I've approximated them with a stepping load test. They're easy to measure in-app, though. > > Incidentally, did anyone notice that Intel revived their old “optimised for the Internet” marketing fluff for their new Kaby Lake CPUs? Last seen for the Pentium III, and just as disingenuous. > > - Jonathan Morton > > "Intel inside" is a warning label (;-)) --dave -- David Collier-Brown, | Always do right. This will gratify System Programmer and Author | some people and astonish the rest davecb@spamcop.net | -- Mark Twain