Assume that you use R Services in Microsoft SQL Server 2017. When you run an R script in parallel execution, the script fails.
The fix for this problem is included in Cumulative Update 6 for SQL Server 2017.
About SQL Server 2017 builds
Each new build for SQL Server 2017 contains all the hotfixes and security fixes that were in the previous build. We recommend that you install the latest build for SQL Server 2017.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Learn about the terminology Microsoft uses to describe software updates.