Re: Linux TCP - unexpected retransmissions



If you have already checked all the stats available in Linux (netstat
-s and ethtool) and they are indeed clean, and then have checked the
stats on the switches (for those situations were switches were used),
and a tcpdump trace, or perhaps better still some external packet
sniffing with a sufficinelty powerfull third system (and perhaps a
hub) shows actual symptoms of packet loss, then it would seem that you
have encountered a situation where there are points in the stack which
can drop packets, but not increment a stat.

That would be a bug.

You may need to start perusing the source of the entire path looking
for places where this might be the case. You would then need to
kludge-in some counters of your own (perhaps just simple printk's even
as a start) to see what might be going-on. If you get your Linux bits
from a commerical source, you could fire-up your support contract and
start getting them to do some of that - the source code perusal and
perhaps quick and dirty counters at least.

rick jones
--
oxymoron n, Hummer H2 with California Save Our Coasts and Oceans plates
these opinions are mine, all mine; HP might not want them anyway... :)
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...
.



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