A couple of years ago I tested a Windows server 2016 deployed with an REFS and NTFS disk on the same hardware, NTFS using 64k allocation unit size. REFS tested much slower using a sqliosim benchmark. It was also noticed by users who performed large data loads. Switching to NTFS resolved it, so I've never touched it since.Should you use refs with SQL Server?
This leads to NTFS operations still consistently outperforming peer ReFS operations. ReFS does generally scale similarly to NTFS, plateauing, peaking, and declining at roughly the same configurations, but with consistently lower performance metrics. In short, I’m not recommending using ReFS with SQL Server just yet, even though it’s supported.Is it the end of NTFS?
But, that does not mean that NTFS has reached its end. ReFS has staggeringly higher limits, but very few systems use more than a fraction of what NTFS can offer. ReFS does have impressive resilience features, but NTFS also has self-healing powers and you have access to RAID technologies to defend against data corruption.What makes Refs the best choice for Windows Server 2019?
Starting from the innovations introduced with Windows Server 2016 and the more recent ones of Server 2019, we can highlight some of the key aspects that can make ReFS the best choice in many scenarios. Performance and scalability are certainly one of the strengths of ReFS, being able to manage large amounts of data very quickly and optimally.