Inconsistent JPT results and poor overall performance

[Andrzej Skrobak]

Hi everyone,
im experiencig major performance issues on Jira 7.6 on premise instance and to determine the root cause im performing JPT on test instance. Both instances have a few vCores and plenty of RAM (around 12 GB). What i have done so far is changed garbage collector to G1GC, performed update to 7.13 on test instance. Results of JPT are changing without any change in configuration, turning G1GC caused results to get worse for several test runs. There are 518 custom fields configured and around 60k issues in 620 projects and 70 workflows. Database is set on MSSQL on premise server.Some results are so low due to low number of active users (number of active users dropped to 1 from 40). I would appreciate your guidance and advice in performance improvement. Could you please recommend any useful tool to manage custom fields? 

Kind regards

[Gonchik Tsymzhitov]

I do via 

https://github.com/atlassian/dc-app-performance-toolkit

and copy of prod data