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From: Mohammad El-Shabani <mohammad.elshabani@gmail.com>
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Subject: [dpdk-dev] librte_pmd_ixgbe implementation of
	ixgbe_dev_rx_queue_count
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Hi,
Looking into why it hurts performance, I see that ixgbe_dev_rx_queue_count
is implemented a scan of elements of rx descriptors, which is very
expensive. I am wondering why its implemented the way it is. Could it not
just read the head location from the driver?

Thanks!
Mohammad El-Shabani