matching performance

John Hascall john at
Fri Sep 24 11:43:27 UTC 2010

> A sub-class is probably going to be more efficient as it uses a hashed 
> lookup. Of course, unless there were many 000's of such entries it's not 
> likely to make much difference either way on decent hardware. eg:
> class "dns1" {
> 	match option agent.remote-id;
> 	option domain-name-servers;
> }
> sub-class "dns1" 0A:00:3E:F0:5C:84;
> sub-class "dns1" 0A:00:3E:F0:7C:7C;
> sub-class "dns1" 0A:00:3E:F0:6D:3E;
> Of course you can have as many different classes and sub-classes as 
> required. You could even have the sub-class statements in a separate 
> file that you included, if you wanted to generate them with a script, 
> for example.

A subclass (no '-', BTW) is definitely the way to go.  It's cleaner
and more efficient (I just looked and we have nearly 40,000 subclasses
in our config file with no performance issues at all).


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