dummynet dropping too many packets

rihad rihad at mail.ru
Tue Oct 6 13:15:07 UTC 2009


Eugene Grosbein wrote:
> On Tue, Oct 06, 2009 at 02:21:38PM +0500, rihad wrote:
> 
>> Is there some limit on the number of IP addresses in an ipfw table?
> 
> No, generally handles much more. Please show your ipfw rule(s)
> containing 'tablearg'.
> 

01031         x            x allow ip from any to any
01040         x            x skipto 1100 ip from table(127) to any out 
recv bce0 xmit bce1
01060         x            x pipe tablearg ip from any to table(0) out 
recv bce0 xmit bce1
01070         x            x allow ip from any to table(0) out recv bce0 
xmit bce1
01100         x            x pipe tablearg ip from any to table(2) out
65535         x            x allow ip from any to any



table(127) contains country-wide ISPs' netblocks (under 100 entries).
table(0) and table(2) contain same user IP addresses, but different pipe 
IDs - normally around 3-4k entries each.

Now please pay special attention to rule 1031. I've added it to bypass 
dummynet and stop packets from being dropped for now. Normally the rule 
isn't there.

As I found out today after rebooting, drops only start occurring when 
the number of entries in table(0) exceeds 2000 or so (please see my 
previous email). Maybe it's a coincidence - I don't know. Global traffic 
load doesn't matter - it was approximately the same before and after the 
drops (around 450 mbit/s).


More information about the freebsd-net mailing list