Date: Mon, 18 Sep 2000 21:31:17 -0400 (EDT)
From: jamal <hadi@xxxxxxxxxx>
My testing with the included scheme (#ifdef RAND_LIE) indicates
that fairness infact goes up; however, the overall throughput when
only one interface is utilizing the system goes down under heavy to
moderate congestion. I am including it here as a way to highlight
the problem. I think there could be better ways to do this. Code
is included and can be turned on by defining RAND_LIE in dev.c
Why not keep a counter per-device.
This counter is an atomic_t and initially zero.
When a packet is given to netif_rx and becomes part of the backlog
this counter is incremented.
When a packet leaves the backlog, this same counter is decremented.
You can use this counter to approximate queue percentages per-device
and use this to decide who gets the little white lies.
Questions are whether this will be cheaper than calling net_random()
occaisionally and actually more interesting would be a scheme which
did not hurt the single interface case. :-(
Later,
David S. Miller
davem@xxxxxxxxxx
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