Sean Chittenden sean at
Wed Jun 30 10:33:06 PDT 2004

> Thank you very very much.. but sysctl sendspace/recvspace will be the 
> limits then?


> can I set SO_SNDBUF to something higher than tcp.sendspace?

Hrm... tcp(4) is a bit ambiguous about this:

    MIB Variables
      The TCP protocol implements a number of variables in the 
      branch of the sysctl(3) MIB.

      TCPCTL_SENDSPACE   (sendspace) Maximum TCP send window.

      TCPCTL_RECVSPACE   (recvspace) Maximum TCP receive window.

I don't know if setsockopt(2) will allow you to exceed these values.  I 
don't see anything in setsockopt(2) that suggests that you can't exceed 
TCPCTL_SENDSPACE with setsockopt(2).

> I'm thinking of setting tcp.sendspace to 64k and using setsockopt on 
> ircd to set it to 2k (why an irc connection would need more than 
> that?), so apache will use 64k and ircd 2k.. am I right? :P

This is a wise course of action given the uncertainty of setsockopt(2) 
and the net.inet.tcp.* interaction.  I'd grep through the source and 
give you a definitive answer but am busy/too lazy at the moment.  :)  

Sean Chittenden

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