We found big load different between Jmeter5.0 and Jmeter 5.3 the jmx file was captured on Jmeter 5.3 We can reproduce all the time.
Thanks for the report. There is not enough information in this request, that we can help you. Please have a look at https://jmeter.apache.org/issues.html (especially the paragraph titled "Required Information for bug reporting"). Always remember, we can't see, what you are doing. We don't know, what you are doing. You have to explain everything to us :) "It is slow" is not enough.
This issue has been migrated to GitHub: https://github.com/apache/jmeter/issues/5500