Processes, Threads and IPC

These pages contain the documentation for Gecko’s architecture for platform process and thread creation, communication and synchronization. They live in mozilla-central in the ‘ipc/docs’ directory.

• IPDL: Inter-Thread and Inter-Process Message Passing
  • The Idea
  • The Approach
    • The Steps To Making A New Actor
  • The Protocol Language
    • Using The IPDL compiler
    • Referencing Externally Defined Data Types: IPDL Includes
    • Namespaces
    • Generating IPDL-Aware C++ Data Types: IPDL Structs and Unions
    • Defining Actors
    • Declaring IPDL Messages
    • IPDL Syntax Quick Reference
  • The C++ Interface
    • ParamTraits
    • IPDL Structs and Unions in C++
    • Actors and Messages in C++
    • Actor Lifetimes in C++
  • Top Level Actors
    • Value of Top Level Actors
    • Creating Top Level Actors From Other Actors
    • Creating First Top Level Actors
  • PBackground
  • IPDL Best Practices
  • The Old Ways
  • The FUD
  • The Rest
    • Nested messages
    • Message Logging
• Gecko Processes
  • Before Creating a New Process
  • Firefox Process Hierarchy
  • Adding a New Type of Process
    • Common Architecture
    • Process Bookkeeping
    • Creating the New Process
    • Initializing the New Process
    • Destroying the New Process
    • Creating a New Top Level Actor
    • Connecting With Other Processes
    • Completing the Sample
    • Running the Sample
  • Debugging Process Startup
    • Debugging with IPDL Logging
    • Early Debugging For A New Process
• Shutdown handling of processes
  • Shutdown flavors
    • Main process Shutdown
    • ProcessChild Shutdown
  • Make your Code Shutdown aware
    • Late Initialization and/or Resurrection Checks
    • Selfmade Shutdown Handler: Observe a Shutdown Topic
    • Simple Shutdown Handler for C++: RunOnShutdown and ClearOnShutdown
    • Full blown Shutdown Handler: AsyncShutdown Blockers
    • Test harness special cases
  • Shutdown Hang Detection
    • Main Process Hangs
    • Content Process Hangs
• Utility Process

For inter-process communication involving Javascript, see JSActors. They are a very limited case, used for communication between elements in the DOM, which may exist in separate processes. They only involve the main process and content processes – no other processes run Javascript.