Hello ,

I need some advise .Customer is using Vplex with VNX as backend storage .

The environment is  facing huge performance issue  every week that is  impacting the  production . ISAP application is used and hosted on VMs The SAP engineer  ran application tests and statpack  report from the  server, which points to Log File Sync waits caused by very slow I/O .He also provided the details of the lun that has latency of ~30ms .

I wasn't initially involved in the troubleshooting , and the storage engineer who worked on it has left . As a workaround  he  changed  the Lun policy to highest available tier  that brought down the response time . Last week customer again encountered high response time .There was a backup job that was running in  parallel with application jobs. When the  backup job was cancelled there was  significant improvement in the  response time. As per SAP team this happens every monday  and going on since past one month .

Per the storage engineer update he promoted the luns to extreme performance tier to bring down the response time

Has anyone encountered similar issue ? I am not sure how promoting the luns to extreme performance can stop the occurrence .

Also, let me know the things I can check from my end to know whether the issue is actually from storage .Customer need a permanent fix .

Thank you .