SQL Server is a product with a 30 years long history of development. We are speaking about millions of lines of code on a single operating system (Windows). The logical question is how Microsoft successfully ports those millions of lines of code to the Linux platform so fast. SQL Server on Linux officially became public in the autumn of 2016. This process would take years of development and investment. Fortunately, it was not so hard.
From version 2005, the SQL Server database engine had a platform layer called SQL operating system (SOS). It is a layer between the SQL Server engine and the Windows operating systems.
The main purpose of SOS is to minimize the number of system calls by letting SQL Server deal with its own resources. It greatly improves performance, stability, and the debugging process. On the other hand, it is platform dependent and does not...