Robert:

I thinkg we'd need to see many interations oscilating between name vs IP,
to make a reasonable conlusion.

Effectively any one single packet could have taken significanlty longer.

The reason could be any compounded number of things. i.e. if foo were low
on memory the act of freeing / releasing / swaping out the gethostbyname
(not the DNS lookup) to free up memory to update the arp table and
respond, freeing buffer cache.  Then any other network traffic; WINS
broadcasts, etc.

pinging localhost v 127.0.0.1 my also eliminate extranious anomilies too.

I thing ping v name vs ping v IP is only an anomily.

In my tests  the diff between IP v name where nominal:

[EMAIL PROTECTED] ~]# ping -f -c 1000 occam599
PING occam599 (10.144.24.156) 56(84) bytes of data.

--- occam599 ping statistics ---
1000 packets transmitted, 1000 received, 0% packet loss, time 16333ms
rtt min/avg/max/mdev = 0.007/0.010/0.067/0.005 ms, pipe 2, ipg/ewma
16.350/0.010 ms

[EMAIL PROTECTED] ~]# ping -f -c 1000 10.144.24.156
PING 10.144.24.156 (10.144.24.156) 56(84) bytes of data.

--- 10.144.24.156 ping statistics ---
1000 packets transmitted, 1000 received, 0% packet loss, time 15978ms
rtt min/avg/max/mdev = 0.007/0.009/0.069/0.004 ms, pipe 2, ipg/ewma
15.994/0.009 ms

[EMAIL PROTECTED] ~]# ping -f -c 1000 10.144.24.156
PING 10.144.24.156 (10.144.24.156) 56(84) bytes of data.

--- 10.144.24.156 ping statistics ---
1000 packets transmitted, 1000 received, 0% packet loss, time 15845ms
rtt min/avg/max/mdev = 0.007/0.009/0.037/0.003 ms, pipe 2, ipg/ewma
15.860/0.010 ms

[EMAIL PROTECTED] ~]# ping -f -c 1000 occam599
PING occam599 (10.144.24.156) 56(84) bytes of data.

--- occam599 ping statistics ---
1000 packets transmitted, 1000 received, 0% packet loss, time 15832ms
rtt min/avg/max/mdev = 0.007/0.009/0.059/0.003 ms, pipe 2, ipg/ewma
15.848/0.008 ms


Cheers;

E!



>
> What's wrong with this picture?
>
> Notice the time if I ping a machine by IP address:
>
> $ ping -f -c 1000 10.4.0.4
> PING 10.4.0.4 (10.4.0.4) 56(84) bytes of data.
>   --- 10.4.0.4 ping statistics ---
> 1000 packets transmitted, 1000 received, 0% packet loss, time 383ms
> rtt min/avg/max/mdev = 0.086/0.332/29.934/2.000 ms, pipe 2, ipg/ewma
> 0.384/3.827 ms
>
> Now, notice the time if I ping by name:
>
> $ ping -f -c 1000 foo
> PING foo.com (10.4.0.4) 56(84) bytes of data.
> --- foo.com ping statistics ---
> 1000 packets transmitted, 1000 received, 0% packet loss, time 24598ms
> rtt min/avg/max/mdev = 0.092/0.100/0.133/0.010 ms, ipg/ewma
> 24.622/0.100 ms
>
> A 64 fold increase in the amount of time.
>
> Any thoughts?
>
> Regards,
> - Robert
> http://www.cwelug.org/downloads
> Help others get OpenSource software.  Distribute FLOSS
> for Windows, Linux, *BSD, and MacOS X with BitTorrent
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>
>
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