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Re: NetBSD 5.1 TCP performance issue (lots of ACK)

To diagnose this, I recommend making a tcpdump of the traffic with

tcpdump -w TRACE tcp

and then using  tcpdump2plot in graphics/xplot-devel.

I am not clear if graphics/xplot-devel (or /xplot) has caught up to
minor changes in NetBSD tcp

These plots are not 100% obvious how to read, but I'm happy to look at
them if you can provide the above trace file.   Counts are useful, but
this lets you see the fine-grained behavior of what got sent when.

From the stats, it looks like there is loss in the data stream causing
SACK.  But I don't see how there would be 237850 pure acks for ~98K data
packets; there should be more like 49K.

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