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Date:      Fri, 20 Nov 2009 14:35:22 -0700 (MST)
From:      Brett Glass <>
Subject:   kern.polling.lost_polls
Message-ID:  <>

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I've been experimenting with using device polling on a router with six Ethernet
interfaces that handles lots of traffic. I turned polling on, and set HZ=4000
to minimize latency and ensure that enough time was allocated to handle all of
the incoming packets. But the sysctl variable kernel.polling.lost_polls keeps
incrementing! The documentation of this variable isn't very good, so I am not
sure what this means. Does it mean that I should set kern.hz lower (perhaps
to 2000) and kern.polling.burst_max higher? Or that running the interfaces
in interrupt-driven mode would be more effective? How can I tell? (Feel free
to ask for more information about the hardware or kernel config if it would
help you to provide a good answer.)

--Brett Glass

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