From what we gathered, limitation on IGMP subscriptions can be set by using the following parameter: igmp_max_memberships (default to '20'). However, on some of our servers where we left the default value, we noticed that our ethernet card is subscribed to more than 700 different IGMP Groups:
# head -4 /proc/net/igmp: Idx Device : Count Querier Group Users Timer Reporter 1 lo : 0 V3 010000E0 1 0:00000000 0 2 eth0 : 711 V2
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