Esat Erkec walks us through Delayed Durability in SQL Server:
In this article, we will learn the Delayed Durability feature that helps to improve transaction log file write throughput in SQL Server.
OLTP (Online Transaction Processing) databases should process a huge number of transactions within the shortest time and concurrently. Therefore, the transaction completion time becomes more important for the performance of the OLTP databases. Particularly for SQL Server, the transaction log (T-log) file configuration will play a key role in the performance of the transaction completion times because the write throughput to the log file directly affects the application response times.
This is a feature which might be useful in specific scenarios, but I’m always concerned about that risk of data loss.