Hping/Ping

[Ingo Flaschberger]

Dear Dave,

> intr_queue_drops was rising very quickly, after changing queue_maxlen to 500
> (from 50) the problems all went away. What's a reasonable value for that for
> a high load box (5000+ interrupts a second) ?

http://devwiki.pfsense.org/Tuning?show_comments=1
they set it to 3000

intel em-cards have a buffer of max. 4096

some more talks & tuning:
http://osdir.com/ml/freebsd.devel.net/2002-10/msg00072.html
http://osdir.com/ml/freebsd.devel.net/2002-10/msg00104.html

> Also, while over a 1000 pings have gone through fine now, a minute or two
> after I made the change I saw this --
>
> 64 bytes from x.x.x.x: icmp_seq=25 ttl=255 time=0.465 ms
> ping: sendto: No buffer space available
> ping: sendto: No buffer space available
> ping: sendto: No buffer space available
> ping: sendto: No buffer space available
> ping: sendto: No buffer space available
> ping: sendto: No buffer space available
> ping: sendto: No buffer space available
> 64 bytes from x.x.x.x: icmp_seq=35 ttl=255 time=0.294 ms
>
> It hasn't happened again (and I hope it doesn't) - but is that something I
> should look for?

try todo a netstat -m when you get the buffer errors.

and increase:
net.inet.tcp.sendspace

just to be shure, you have a 1000mbit link?


Kind regards,
 	Ingo Flaschberger