Le mardi 30 novembre 2010 à 09:56 -0800, Rick Jones a écrit :

Short of packet traces, taking snapshots of netstat statistics before and after 
each netperf run might be goodness - you can look at things like ratio of ACKs 
to data segments/bytes and such.  LRO/GRO can have a non-trivial effect on the 
number of ACKs, and ACKs are what matter for fast retransmit.

netstat -s > before
netperf ...
netstat -s > after
beforeafter before after > delta

where beforeafter comes (for now, the site will have to go away before long as 
the campus on which it is located has been sold) 
ftp://ftp.cup.hp.com/dist/networking/tools/  and will subtract before from after.

happy benchmarking,

Yes indeed. With fast enough medium (or small MTUS), we can enter in a
backlog processing problem {filling huge receive queues}, as seen on
loopback lately...

netstat -s can show some receive queue overrun in this case.

    TCPBacklogDrop: xxx