Hi
I checked at first netstat -ni and found Rx dropped and RX overruns on eth1 and eth5
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I increased rx-ringsize first to 2048 and then to 4096.
Now there are no drops but it did not helped
second - I run fwaccel stats -s
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I tried to reduce the F2F traffic - now there is about 12%
third - I disabled almost all blades.
fourth - Changed encryption settings
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fifth - increased /decreased MTU ( try 1410,1480, 9000)
I also checked sk165853 but it looks ok
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I also use this manual - sk61221 - Issues requiring adjustment of the Maximum Segment Size (MSS) of TCP SYN and TCP SYN-ACK p...
Now
fw_clamp_tcp_mss=1
no improvement in sight or only upload
I decided to order an MTR test between these two sites from ISP
Tomek