Azure SQL Database Managed Instance (public preview) is a fully-managed SQL Server instance in Azure cloud. In the current public preview there are some known issues and bugs that will be fixed during public preview period. One of the potential issues is number of files and max_size that is set on tempdb. In this post,... Read more

https://blogs.msdn.microsoft.com/sqlserverstorageengine/2018/03/13/how-to-configure-tempdb-in-azure-sql-managed-instance/