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Re: netstat -m issue on evbarm



Nick Hudson <skrll%netbsd.org@localhost> writes:

> This is just a symptom of how usb network vs non-usb network drivers
> work.

Expanding on this, it is typical for PCI network drivers (e.g. bnx, wm)
to allocate many mbufs/clusters (256 or 512 per interface) and place the
clusters in the receive descriptor ring, allowing the interface to DMA
packets when they arrive, and then interrupt which has the driver send
the packets up the stack and replenish the waiting memory.   So really
the odd thing is that idle systems with PCI interfaces tend to have
buffers in use.

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