AIX network debugging

Since a couple of day at work I had to investigate on some network issues for an application, it seems that we have a strange ARP configuration that may be the main issue… by the way, I discovered another strange thing where icmp packets sent in burst mode (like a flood) are lost at variable rates. Here is the note on my investigations

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Nmon cpu_summ vs cpu_all in a SMT environment

In a SMT CPU you have real primary core and SMT core, all can have process allocated to them but the performance of the primary logical processor compared to the SMT one are not equivalent. Usually the SMT power is about 20-30% of the primary one.

This impact the way the performance is measured

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