Re: IGMP Join dropping multicast packets

[Eric Dumazet <dada1@cosmosbay.com>]

Eric Dumazet a écrit :
> Dave Boutcher a écrit :
>> On Sat, Mar 14, 2009 at 9:37 PM, Eric Dumazet <dada1@cosmosbay.com> wrote:
>>> Dave Boutcher a écrit :
>>>> I'm running into an interesting problem with joining multiple
>>>> multicast feeds.  If you join multiple multicast feeds using
>>>> setsockopt(...,IP_ADD_MEMBERSHIP...) it causes packets on UNRELATED
>>>> multicast feeds to get dropped.  We have a multicast feed on a rock
>>>> solid network, and we were very surprised to see dropped packets.  The
>>>> cause was a different process/program being run by a different user
>>>> joining a bunch of mulitcast feeds.
>>> I could not reproduce the problem on my machines (bnx2 adapter), even if changing
>>> NUMSOCK from 55 to 200 in joiner.c
>> Thanks for trying Eric.  Based on your email I did some more testing
>> and thus far I've
>> only recreated this on x86_64 arches, not on i386.  Which arch did you
>> try it on?
> 
> I tried both, 32 and 64 bit kernels. No problems so far.
> 
> Could you post a linux kernel .config of a non 'working' machine, and dmesg output ?
> 

Also, is using a third machine to start your joiner program is able to trigger
packet losses too ?