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Comment by andreyf | Hacker News Reader

This is what a quick comparison looks like from NYC (in ms):

                    Level 3   Google   OpenDNS
    lifehacker.com  21        22       19 
    facebook.com    20        22       19 
    manu-j.com      21        44       42 
    reddit.com      30        73       20 
    tb4.fr          125       22       157 
    bbc.co.uk       103       22       98

The IP's used are 4.2.2.2, 8.8.8.8, and 208.67.222.222, respectively.

Using the script provided here: http://www.manu-j.com/blog/opendns-alternative-google-dns-ro...

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Doing a single query for each domain isn't entirely fair.

    $ dig tb4.fr @208.67.222.222 | grep Query
    ;; Query time: 274 msec 
    $ dig tb4.fr @208.67.222.222 | grep Query 
    ;; Query time: 9 msec 
    $ dig tb4.fr @208.67.222.222 | grep Query 
    ;; Query time: 9 msec 
    $ dig tb4.fr @208.67.222.222 | grep Query 
    ;; Query time: 36 msec

Also, query time only tells you how long the server took to respond, and doesn't include network latency.

Obviously subsequent queries are going to be faster - at that point it's cached. That's the point of aggressive/speculative caching: it's so the first (and in practice this will be your only) query is faster. If you want to accurately average across multiple measurements, you need to space those measurements hours or days apart.

What you really want to do is log performance under real conditions over an extended period of time and then evaluate the results.

Given that the differences in query time between various DNS solutions are significant but minor, you will almost certainly find differences in performance that you hadn't thought about.

I'm updating the post (http://www.manu-j.com/blog/opendns-alternative-google-dns-ro...) as results keep coming in (India, Italy, NYC, Houston). From the looks of it, google is the best for international users and Level 3 (4.2.2.2) or openDNS for americans.

From London:

                    Level 3  Google  OpenDNS
    lifehacker.com    35       29      26
    facebook.com      31       45      18
    manu-j.com        30       41      38
    reddit.com        42      350      17
    tb4.fr            36       22      25
    bbc.co.uk         45       39      26

OpenDNS has servers here in London, so they put up a fairly good showing. And obviously there's some jitter - the 350ms reddit result is an anomaly - but a few other runs turned up 216ms and 378ms - must be something odd about it.

    Level 3       lifehacker.com       29ms
    Google        lifehacker.com       20ms
    OpenDNS       lifehacker.com       15ms
    
    Level 3       facebook.com         94ms
    Google        facebook.com         20ms
    OpenDNS       facebook.com         18ms
    
    Level 3       manu-j.com           32ms
    Google        manu-j.com           46ms
    OpenDNS       manu-j.com           14ms
    
    Level 3       reddit.com           30ms
    Google        reddit.com           22ms
    OpenDNS       reddit.com           16ms
    
    Level 3       tb4.fr              100ms
    Google        tb4.fr               21ms
    OpenDNS       tb4.fr               14ms
    
    Level 3       bbc.co.uk           132ms
    Google        bbc.co.uk            21ms
    OpenDNS       bbc.co.uk            15ms

Nottinghamshire, UK. OpenDNS a clear winner…

Madrid, Spain.

  Level 3    lifehacker.com   355 msec
  Google     lifehacker.com   37 msec
  OpenDNS    lifehacker.com   30 msec

  Level 3    facebook.com     46 msec
  Google     facebook.com     40 msec
  OpenDNS    facebook.com     32 msec

  Level 3    manu-j.com       196 msec
  Google     manu-j.com       37 msec
  OpenDNS    manu-j.com       32 msec

  Level 3    reddit.com       44 msec
  Google     reddit.com       60 msec
  OpenDNS    reddit.com       29 msec

  Level 3    tb4.fr           89 msec
  Google     tb4.fr           36 msec
  OpenDNS    tb4.fr           31 msec

  Level 3    bbc.co.uk        47 msec
  Google     bbc.co.uk        37 msec
  OpenDNS    bbc.co.uk        30 msec

OpenDNS wins

Fascinating. It's interesting to see that their times aren't always the fastest, but they seem able to keep responses speedy on the sites the other two struggle with (bbc and tb4). Maybe that's the prefetching at work?

It's a bit hard to do the math in bash, but you'd also probably want to determine the mean and standard deviation for a population of checks (at least 10 or so).

You could calculate it across a lot of domains, or calculate it with a lot of checks to one server.

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