From: "Qinghua(Kevin) Ye" <[EMAIL PROTECTED]>
Date: Tue, 5 Jul 2005 16:19:27 -0600

> Compared to NAPI, click polling will disable Nic interrupts during its
> operation, even there is no any packets in the rx buffer.

This destroys latency if you only recheck the RX buffer using
timer interrupts.  Even with HZ=1000, on gigabit links your packet
latency will be terrible.  We've tried this before.

> The other difference is its reusage of packet buffer.  It implements
> its own buffer recycle scheme. So once there are some packets
> received by tg3_rx_poll(), it will refill the DMA ring by
> tg3_rx_refill() by allocate buffer from its recycle queue. And once
> the packet is send out by tg3_tx_queue(), and cleaned by
> tg3_tx_clean, it will be collected into recycle queue.

This is interesting as a generic facility usable by drivers.
It needn't be CLICK specific.
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