Problem:

Customer reports packet loss or high latency( 10times than usual) or bad application performance on a site and it happens in the interval of 5 mins or you see a pattern on the interval

Troubleshooting:

Ask customer to initiate a ping from a remote site to the problematic site’s LAN interface and observe when the latency starts rising up

(E.g)

Table

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Do top -H and Press 1

Watch it for sometime for atleast 2-3 iterations. If you get to see WT-0 always goes high with CPU consumption every time the above problem occurs


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Then do "sudo perf top" on a different tab, when the WT-0 goes high.


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If you see lef_mstats being at the top until the WT-0 is high

Then it is due to a bug – 65904- Fixed in 20.2.4, 21.1.3


Workaround:

Make the value to “ 0 “ on the below fields under LEF tab and disable “stream tcp evasion detection”

Graphical user interface, application

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Enabling the Isolate CPU would improve the performance too