I was doing some searching about Out of Order packets and came across this thread that was apparently posted to this list. I didn’t see any real answer to it so I’m posting my findings. I hope this is not too old :-/ .
http://www.wireshark.org/lists/wireshark-users/200701/msg00060.html
I can tell you I found the cause of this in my case. I have a Cisco 6509 connected to a Cisco 3560 on a gig port. I saw significant Output drops on the 6509 end because the buffers in a 3560 cannot keep up with what a 6509 can push. I did a packet capture and found I am getting 100Mbps in Out of Order packets…yuck. The 3560’s are not a data center class switch and we should not be using them in our case.
The 1st 24 ports of the 3560 all share a 2MB buffer, the 2nd 24 ports share another 2MB buffer. That’s not much at all.
Contrast that with the 6509’s (using WS-X6748’s) and they have a 1.3MB buffer per port and you can clearly see the 3560 cannot keep up.
All Gig ports are not created equally :-/.
Anyway, I hope this helps.
Thank you,
-Steve