where is net.inet.udp.sendspace?

[Michael R. Hines]

I see. I'll modify the application.

Is there also a way of controlling the kernel's UDP buffer queue - the 
queue used to store user-space packets before they're put on the link?

I've seen other mailing lists through searching where users listed the 
existence of a "udp.sendspace". Where those just patched or altered FreeBSD 
versions?

Thanks for your reply,
- Michael

At 04:53 PM 2/6/2005, you wrote:
>On Sun, Feb 06, 2005 at 07:54:15AM -0500, Michael R. Hines wrote:
> >
> > On my 5.3-RELEASE system,   sysctl -a | grep net | grep space gives:
> >
> > net.local.stream.sendspace: 8192
> > net.local.stream.recvspace: 8192
> > net.local.dgram.recvspace: 4096
> > net.inet.tcp.sendspace: 32768
> > net.inet.tcp.recvspace: 65536
> > net.inet.udp.recvspace: 42080
> > net.inet.raw.recvspace: 8192
> >
> > Where is udp.sendspace?
> >
> > I'm having some UDP "No buffer space available" problems, but the precise
> > sysctl variable corresponding to the problem doesn't seem to exist.
> >
> > Anyone else have this mysterious problem?
>
>UDP is not buffered in the kernel like TCP is, so a sendspace sysctl
>is not possible.  When the interface queue becomes full (i.e. you are
>sending data to the interface at a greater rate than it can put it on
>the wire), you will see this error message, and your application needs
>to be able to handle it.
>
>Kris

/*********************************/
Michael R. Hines
Grad Student, Florida State
Dept. Computer Science
http://www.cs.fsu.edu/~mhines/
Jusqu'à ce que le futur vienne...
/*********************************/