Course Code: 928
Length: 5 days

This course is designed to examine the components, structures and mechanisms of the Compaq OpenVMS Alpha operating system. It is intended for those students requiring an extensive understanding of these areas.

This course discusses some of the interrelationships between code, data structures and synchronization techniques used in the operating system. System managers and application programmers will find useful technical background to assist them in their roles. Topics will include the effects of altering certain sysgen parameters, resource allocation and implications of granting privileges.

In addition to flow descriptions and pictorial representations of the data structures and code that form Compaq OpenVMS, the course will use the System Dump Analyzer and privileged code to illustrate the concepts presented in the course materials. The majority of code will be written in DEC C and will be current as Compaq OpenVMS Version 7.2.

Who Should Attend

• This version of the OpenVMS Alpha internals course is geared toward the system programmer, i.e. someone who will be writing code that will run in kernel or executive mode.
• Computer professionals who wish to pursue the certification exam for Compaq OpenVMS.

Prerequisites

• The ability to read, and ideally write code, in VAX macro.
• Completion of the Programming with system services courses.
• Ability to program in DEC C.

Benefits of Attending this Class

On completion of the course, the attendee should be able to:

• Describe the data structures that constitute a process and examine them using SDA.
• Describe the OpenVMS scheduling mechanism and change system parameters which affect scheduling.
• Describe the reasons for processes entering and leaving wait states.
• Describe and examine the contents of OpenVMS virtual address space.
• Analyze process and system stalls caused by process resource wait states.
• Describe the activities occurring in the various OpenVMS access modes.
• Describe flow through the SYS$ASSIGN and SYS$QIO system services.

Course Contents

• REVIEW OF INTERNALS I
• EXECLETS
  • Modular Executive
  • Bound Procedure Descriptors
  • Granularity Hint Regions
  • Building an Execlet
• DEBUGGING TOOLS
  • Introduction to Crash Dump Analysis
  • SDA/CLUE
  • Debuggers
  • DELTA
  • XDELTA
  • Source Code Debugger
• OPENVMS SCHEDULING
  • Thread Wait States
  • Common Event Flag Wait Queue
  • Computable Queues (also COMO)
  • The Scheduler
  • Boosting Software Priority
  • Report System Event (RSE)
  • Quantum End and Wait State Activities
• RESOURCE WAIT STATES
  • Resource Wait States
  • RWAST Waits
  • RWMBX Waits
  • RWMPB Waits
  • RWSCS Waits
  • MUTEX Waits
• PROCESS/KERNEL THREAD CREATION AND DELETION
  • Process Creation
  • Allocation of New Data Structures
  • PQL Parameters
  • Process Types
  • Loginout
  • Starting an Interactive Job
  • Starting a Batch Job
  • Process Deletion
  • Kernel Thread Creation
  • Kernel Thread Deletion
• I/O: CHANNEL ASSIGNMENT AND FDT ROUTINES
  • Paths from I/O Initiation to Completion
  • Channel Assignment
  • $QIO and Function Decision Table Routine Processing
  • Data Structure Support for $QIO and FDT Routines
• I/O: START I/O TO I/O COMPLETION
  • Data Structures Involved in Start I/O Processing
  • General Steps from Start I/O to I/O Completion
  • I/O Post Processing
  • Review of General I/O Data Structures
  • SCS Extensions to the I/O Database
• MULTIPROCESSING ISSUES
  • Timers and Clocks
  • Interprocessor Interrupts
  • SMP Bugchecks
  • Galaxy Issues
• SCHEDULING AND I/O BIG PICTURE
  • Scheduling Subsystem Big Picture
  • I/O Subsystem Big Picture