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Full course price

This short course is designed to provide a detailed look at the various components, data structures, and mechanisms used to implement the OpenVMS operating system. Topics include memory management and Files-11.


  • OpenVMS Programming Features or equivalent experience
  • OpenVMS Internals I and OpenVMS Internals II
  • The ability to read Macro
  • The ability to program in C

Course Objectives

Upon completion of the Internals courses, students should have a big picture of the operating characteristics and interrelationships of the major OpenVMS subsystems.

Course Audience

OpenVMS applications programmers
OpenVMS system programmers

Course Outline

  • Memory management concepts
  • The process header
  • Image activation
  • Image activation and paging
  • Clustering on pagefault reads
  • Evolution of a page table entry
  • Sections
  • The working set list
  • The PFN database
  • The free page list
  • The modified page list
  • Page files
  • Page file internal support
  • Swapper-related activities
  • Shared images and global sections
  • Global section dynamics
  • Shareable image issues
  • Fixup sections
  • OpenVMS shareable images
  • Known files
  • The system header
  • Three-level address translations
  • Image activation
  • Making a page valid
  • A page on the free or modified page list
  • Page file interval support
  • A page no longer in memory
  • Swapping-related structures
  • The system header
  • Working set slots
  • Files-11 concepts
  • File header
  • The Files-11 reserved files
  • The extended QIO procedures
  • File open related data structures
  • Data structures relating to mounted volumes
  • Contiguity and the file system
  • File system caching parameters

Instructors in this course

Dennis O'Brien

40+ years of OpenVMS support and teaching experience, founder of the Bruden Corporation, author of OpenVMS, HP-UX, Tru64 UNIX, and C Programming courses and books.
Languages: English