Memory-Mapped File

Memory-mapped files can be either
  Persisted  : written to disk at regular intervals -- for large file operations , Avoid in memory loss @ crashes
  Nonpersisted.  : in memory throughout the life --for short-duration operations.  - GC will clean

These are managed file access - Not any pInvokes -- No explicit dispose!!

Two types of views
stream access view  -- for sequential access to processes in interprocess communication for non persisted files
random access view. -- Random access views are recommended in persisted access.

The maximum size of memory-mapped view can be
2GB on 32-bit machines
and 264 GB on 64-bit machines.

 Notice these capacities are same as managed heap capacities of respective machines(but no one to garbage collect. Developer need to manage)