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Re: 16 year old bug

On Aug 24, 2010, at 12:25 AM, Joerg Sonnenberger wrote:

> On Mon, Aug 23, 2010 at 11:21:37PM -0400, Thor Lancelot Simon wrote:
>> That's silly.  A bitmask is a bitmask, and there's nothing magical or
>> difficult about masked compare.  Even the bug OpenBSD just fixed -- now
>> that it basically doesn't matter any more -- is hardly complex nor is
>> the fix so.
> The issue with non-cont netmask is that it dramatically complicates the
> lookup code. I'd say that at least 1/3 of the radix tree implementation
> is just related to this "feature".

Even worse, it's inefficient on newer hardware.  Most platforms have a
count-leading operation which dramatically increases the lookups.  Also
knowing the datatype and using datatype specific comparison speeds it
up even more.

I've been removing the use of radix and switching to ptree in the network

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