Re: Route caching ?

Ivo Vachkov wrote:
Actually there is:

struct route_in6 ip6_forward_rt;

that "caches" the last route used (thanks blue !!!) but i think this
technique is pointless in a multiflow traffic.

Yes, this is why OpenBSD got rid of this form of 'route caching'.

Is it reasonable to believe that route caches can improve networking
performance or we should leave it up to the routing table itself ?

I believe that if one goes beyond a single radix trie, as is needed for multi-pathing with multicast and source policy routing, route caching is *required* to achieve good performance.

Also, if FreeBSD moves ARP and NDP out of the radix trie, a route cache would be highly preferable as it amortizes the lock acquisition which would other be required for ARP/NDP/other layer 2 next-hop resolution.

BMS
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