I found this on the Optimizely Support site about MARS being disabled on Linux on DXP: https://support.optimizely.com/hc/en-us/articles/5829401650829-MultipleActiveResultSets-MARS-in-CMS-12-on-DXP
Testing on my windows development machine doesn't seem to raise issues if I have MARS set or not
no, MARS is no longer required for CMS 12. We actively try to disable it because it can cause severe performance issue on Linux. You can run without MARS on CMS 12
I receive the following warning during the initialization phase:
"Database connection is configured to allow MultipleActiveResultSets. Consider disable MultipleActiveResultSets for better performance." (SourceContext: EPiServer.Data.DataInitialization)
According to a forum thread from 2017 MARS is a requirement. Is this still the case for Optimizely 12?