sysctl kern.ipc.somaxconn limit 65535 why?

Chuck Swiger cswiger at
Wed Jan 4 21:35:24 UTC 2012

On Jan 4, 2012, at 12:22 PM, Dan The Man wrote:
> Trying to stress test a framework here that tosses 100k of connections into a listen queue before doing anything, I realize I'll have to use multiple local IPs get get around port limitations, but why is this backlog using a limit?

Even a backlog of a 1000 is large compared to the default listen queue size of around 50 or 128.  And if you can drain 1000 connections per second, a 65K backlog is big enough that plenty of clients (I'm thinking web-browsers here in particular) will have given up and maybe retried rather than waiting for 60+ seconds just to exchange data.


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