Hi Holger & rmg,
no I did’t restart the IS. blocked thread is no longger there because I turn off the service.
I still doesn’t know what is the root cause actually, is it the service design is not good or external factor.
In normal condition, the end to end transaction can take only 1s, but during the slowness it takes almost 20s.
The client now install the monitoring tools called Dynatrace (i’m not sure I can trust this or not), and showing that the slowness comes from the service level. PFA some sample captured by Dynatrace
As you can see from the screenshot (if Im right how to read it):
- Total transaction for 1 service exec time is about 19s
- Response from backend very fast only 134ms
- Some hidden (unknown method) takes almost 14s, don’t know what is that, and causing error:
“[ISS.0088.9145] this SOAPEnvelope object does not contain a valid SOAPHeader object”. The service that throw this is “com.wm.app.b2b.server.ServiceException”
Usually we only blame the resp from backend is slow, but after this monitoring tools, I need to further investigate is there any problem with the product 
Another thing, during peak hours, we have almost 180k transaction per hour. Is it a huge transaction? or some thing that IS can handle normaly?
Best Regards
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