Solution : https://service.sap.com/sap/support/notes/49201 (SAP Service marketplace login required)
Key words : 
------pool        priority  minimum  maximum  minimum  thread  maximum machine        1      2, solution static main storage pools note, active  fault  pages  fault  pages  1      966, system    pool    reserved    max  -----db-----  ---, workload distribution considerably differs, system    pool    reserved    max, classic java virtual machine, j9 java virtual machine, static main storage pools, considerable main storage bottleneck
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