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From: Fred Baker <fred@cisco.com>
To: Jonathan Morton <chromatix99@gmail.com>
Cc: bloat@lists.bufferbloat.net
Subject: Re: [Bloat] Measuring latency-under-load consistently
Date: Sat, 12 Mar 2011 22:54:39 -0800	[thread overview]
Message-ID: <EC6ABAE3-8C60-41BC-BFFE-2473BA900ADA@cisco.com> (raw)
In-Reply-To: <4A5D7592-685F-45CC-9429-CE7FC1A289B5@gmail.com>


On Mar 12, 2011, at 3:03 PM, Jonathan Morton wrote:

> 
> On 13 Mar, 2011, at 12:21 am, Fred Baker wrote:
> 
>> At the risk of sounding like someone mentioning a product, let me mention a product. This assumes, of course, that you're using Cisco equipment. But it allows you to measure delay (how long does it take to get from here to there), jitter (first derivative of delay/dt), and packet loss.
> 
> Ping does most of this, and is available on your actual computer.  A little post-processing of the output gives you jitter, if it doesn't supply that natively.
> 
> The point is, the existing tools don't typically measure latency *under load*.

Actually, SAA uses ping, and is intended precisely to do it under load. Ping is part of the existing traffic, and measures the RTT as experienced by traffic following the same path that the ping does.

Not sure exactly where you're going with that...

  reply	other threads:[~2011-03-13  6:55 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-03-12  0:00 Jonathan Morton
2011-03-12  0:13 ` Rick Jones
2011-03-12  0:45   ` Jonathan Morton
2011-03-12  1:09     ` Rick Jones
2011-03-12  1:44       ` Jonathan Morton
2011-03-12  3:19 ` richard
2011-03-12  3:52   ` Jonathan Morton
2011-03-12  4:04     ` richard
2011-03-12 21:57       ` Jonathan Morton
2011-03-12 22:23         ` richard
2011-03-12 23:58           ` Jonathan Morton
2011-03-12 22:21 ` Fred Baker
2011-03-12 23:03   ` Jonathan Morton
2011-03-13  6:54     ` Fred Baker [this message]
2011-03-13 14:24       ` Jonathan Morton

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