Linux LPF performance

Dubb, Benjamin Benjamin.Dubb at
Mon Oct 5 15:46:38 UTC 2009

This may have been addressed before, but I couldn't find anything...

Our embedded device terminates a good amount of traffic and we are seeing a 5% hit when dhclient is running. It looks like it's due to the LPF rule that gets installed by dhcp. I'm wondering why dhclient on Linux needs to have the PF_PACKET socket opened all the time. Why not close it after the discovery is complete and reopen with a regular socket while the interface is UP and running? Is there a reason that the low level packet interface has to stay open all the time?

If anyone has tried this before, or perhaps there is a patch to get it working, please let me know. I'm on dhcp 3.1.x.


 - Ben

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