Description

In SQL Server, internal latch architecture protects memory during SQL operations. It ensures the consistency of memory structures with read and write operation on pages. Rudimentarily, it has two classes, buffer latches, and non-buffer latches which perform lightweight synchronization in the SQL Engine.

SQL Server locks, discussed in the article All about locking in SQL Server, which is applied on data for the duration of the logical operation to preserve logical transaction consistency. SQL Server latches, however, are a special type of low-level system locks which are held as long as the physical operation lasts on the memory page in order to protect memory consistency