CHAPTER 11 Caching and file systems
The cache manager is a set of kernel-mode functions and system threads that cooperate with the memory manager to provide data caching for all Windows file system drivers (both local and network). In this chapter, we explain how the cache manager, including its key internal data structures and functions, works; how it is sized at system initialization time; how it interacts with other elements of the operating system; and how you can observe its activity through performance counters. We also describe the five flags on the Windows CreateFile function that affect file caching and DAX volumes, which are memory-mapped disks that bypass the cache manager for certain types of I/O. The services exposed by the cache manager are used by all the Windows File System drivers, which cooperate strictly with the former to be able to manage disk I/O as fast as possible. We describe the different file systems supported by Windows, in particular with a deep analysis of NTFS and ReFS (the two mo