Re: unbound EAGAIN sendto errors

On 29/04/2025 18:34, Otto Moerbeek wrote:

On Tue, Apr 29, 2025 at 06:23:34PM +0300, Kapetanakis Giannis wrote:    

On 29/04/2025 18:11, Otto Moerbeek wrote:  

On Tue, Apr 29, 2025 at 04:32:01PM +0300, Kapetanakis Giannis wrote:    

Can it be related to this: dropped due to no socket?  

IIRC OpenBSD does handle sending to a non-blocking socket in the  multi-threaded case very well. If multiple threads try to do that  simulteneously, some of them will get a EAGAIN. To test this  hypothesis, try running with a single thread and see if the errors  disappear.    	-Otto  

  I did run one-thread and the errors where gone...    ok, how I can we go to multiple threads now without the errors?  

  kernel code needs to be written for that. PowerDNS Recursor has an  ugly workaround to just retry a few times on EBUSY.

ok. Why don't I have such errors on another more busy DNS system running with 8 threads?
Is there some other os tuning that could be done?

Even with the one thread i still get dropped due to no socket on netstat  

  AFAIK that's incoming UDP traffic without a matching socket to deliver to.    	-Otto  

Does this mean that those drops are not a problem correct?

is net.inet.udp.sendspace and unbound so-sndbuf: related to this?
Should I get them back to defaults?

Thanks Otto.

G