Re: netstat performance

[Camaleón <noelamac@gmail.com>]

On Wed, 29 Jun 2011 10:15:58 -0600, ChadDavis wrote:

> I notice that the following two invocations of netstat have drastically
> different execution times:
> 
> netstat
> 
> netstat -n
> 
> 
> When you just use numerical addresses, it executes almost instantly, but
> with the domain names and whatever you call those logical names for the
> port numbers, such as 'www', it takes quite while ( 5-10 seconds).
> 
> Not a big deal, but just made me think.  Surely the name resolution
> isn't that costly is it?

That's normal... yes, resolving names takes some time :-)

Another example:

sm01@stt008:~$ time /sbin/route
(...)

real	0m5.018s
user	0m0.000s
sys	0m0.000s

sm01@stt008:~$ time /sbin/route -n
(...)

real	0m0.001s
user	0m0.000s
sys	0m0.000s

Greetings,

-- 
Camaleón