On 4-12-2011 13:01, Sebastian Reitenbach wrote: > the default maximum size of the tcp send and receive buffer used by the > autosizing algorithm is way too small, when trying to get maximum speed with > high bandwidth and high latency connections.
I have tweaked SB_MAX on a system too, but it was for UDP. When running a busy Unbound resolver, the recommendation is too bump the receive buffer to 4M or even 8M. See http://unbound.net/documentation/howto_optimise.html Otherwise a lot of queries are dropped when the cache is cold. I don't think there's a magic value that's right for everyone, so a sysctl would be nice. Maybe separate ones for tcp and udp. I know similar sysctl's have been removed recently, and that they are sometimes abused, but I'd say we have two valid use cases now. So I'd love some more discussion. :-) -- Cam
