Andi Kleen wrote:

David Miller [off-list ref] writes:

quoted

The big problem is that recovery from even a single packet loss in a
window makes us run kfree_skb() for a all the packets in a full
window's worth of data when recovery completes.

Why exactly is it a problem to free them all at once? Are you worried
about kernel preemption latencies?

-Andi

I also wonder how much of a problem this is (for now, with window sizes 
of order 10000 packets.  My understanding is that the biggest problems 
arise from O(N^2) time for recovery because every ack was expensive. 
Have current tests shown the final ack to be a major source of problems?

   -John