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From: Saravana Kumar <maheshmcc39@gmail.com>
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Subject: [dpdk-dev] Clarification on latency at NIC line rate..
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Hi DPDK community,


      I have been experimenting with dpdk eth_tx send on ixgbe pmd (82599 NIC)
      I am seeing the following behavior
         When i pass 1500 bytes at 9.99GB traffic -- latency looks
fine (25 microseconds)
         but when i pass 1500 bytes hitting 10GB traffic(line rate)
-- latency spikes (160 microseconds) and stays forever
         once the traffic returns back to 9.99GB traffic latency also
returns back to normal (25 microseconds)


      Is this expected behaviour ?  Is there any way to reduce the 160
microseconds line rate issue.  Thanks Team

Regards,

Saravanan