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Date: Mon, 1 Jun 2015 11:25:09 +0300
From: Slawa Olhovchenkov <slw@zxy.spb.ru>
To: freebsd-net@freebsd.org
Subject: Intel igb 82576 (netmap mode) and RSS queue issuse with fragmented
 UDP packets.
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I am use Intel 82576 (igb driver) in netmap mode.
I see isssuse: flow routed in different queue depends of IP flags.

For example:

Total 4 queue.
UDP flow. 
SRC: 91.214.70.167:12062 DST: 95.31.64.226:49939 Flags:DF routed to queue 0
SRC: 91.214.70.167:12062 DST: 95.31.64.226:49939 Flags:More_Frags (offset 0, length 1396) routed to queue 3

I understand that next fragment (IP (tos 0x0, ttl 62, id 36361, offset
1376, flags [none], proto UDP (17), length 102) 91.214.70.167 >
95.72.171.116: ip-proto-17) may be routed in different queue, but why
fragment 0 routed to different queue? This is software (driver,
netmap) issuse? Or this is hardware (silicon) isssuse?

What about Intel 10G/40G cards? Chelsio?