Chrome的几类线程

  enum ID {
    // The main thread in the browser.
    UI,

    // This is the thread that interacts with the database.
    DB,

    // This is the "main" thread for WebKit within the browser process when
    // NOT in --single-process mode.
    WEBKIT,

    // This is the thread that interacts with the file system.
    FILE,

    // Used for file system operations that block user interactions.
    // Responsiveness of this thread affect users.
    FILE_USER_BLOCKING,

    // Used to launch and terminate Chrome processes.
    PROCESS_LAUNCHER,

    // This is the thread to handle slow HTTP cache operations.
    CACHE,

    // This is the thread that processes IPC and network messages.
    IO

}