Stan Hoeppner: > What's the CIDR lookup table performance difference between say 256 /32 > entries and a single /24 entry? Is it 256:1?
One /32 match is a probably a little faster than one /24 match. The difference depends on compiler and hardware used. The CIDR implementation could be sped up by using IF/ELSE/ENDIF as in pcre and regexp tables. Adding that is much more work than it was with pcre or regexp. > Or, how about 90,000 /32 > entries vs 60,000 entries that consolidate many of those 90,000 /32s > into larger CIDRs such as /24s and /21s etc? I have no idea what the > total processing time would be on such size CIDRs. Is it small enough > to be irrelevant, or are we looking at something like multiple seconds > per lookup (obviously dependent on hardware)? Try measuring it on a few systems. Wietse