In SQL Server, I normally set the Maximum Server Memory setting to one of the popular best practices, such as leaving 10% or 4GB, whichever is higher.
I have a new server with 64GB RAM. Due to licensing constraints, this server must run the SQL Server database engine, SSIS, and SSAS. SSIS ETLs happen overnight, and users hit the actual database mostly during the daytime. In this scenario, would it be best to leave the default setting so that SSIS can take the memory if needed, and then the database engine can take memory when it needs it?