5th Job and Process Pool (2)

5.6 Job Object events and completion ports

(1) associating the Job object with the completion port object

Jobobject_associate_completion_port JOACP;

JOACP. Completionkey = hJob1; can be used to identify any unique value of a Job Object , where its handle is taken

JOACP. Completionport = HIOCP; handle to completion port

Setinformationjobobject (Hjob,jobobjectassociatecompletionportinformation,

&joacp,sizeof (JOACP));

(2) creates a thread that passes the completion port object as a parameter to the thread function. and GetQueuedCompletionStatus to wait for a notification event for the Job object.

Parameters	Describe
HIOCP	Handle of the completion port object to get the event
Pnumbytestransferred	Event ID to wait for "Events related to Job Object" ①job_object_msg_active_process_limit: The number of active processes in the Job object reaches the limit notification ②Job_object_msg_active_process_zero: Notification when there are currently no active processes in the Job Object ③job_object_msg_end_of_job_time: The Job Object exhausts the specified time period notification. However, the process does not automatically terminate. You can set a new time limit to allow continuation, or call Terminatejobobject to terminate the process. ④job_object_msg_job_memory_limit: The Job Object exhausts the specified memory notification while giving the process ID "Process-related events" ①job_object_msg_new_process: Notifies when a new process joins the Job object and gives the process ID. ②job_object_msg_exit_process: Notifies when the process exits gracefully and gives the process ID. ③job_object_msg_abnormal_exit_process: Notification when the process exits unexpectedly and gives the process ID ④job_object_msg_end_of_process_time: Process runs out of time notifications, process terminates, and process ID is given ⑤job_object_msg_process_memory_limit: The process consumes memory up to the time limit notification, and the process IDis given.
pcompletionkey	Specifies the handle of the job object that triggered the event ( )
poverlapped	In a job event, The value represents which id .
Dwmilliseconds	Used to specify when the caller waits for the port to complete

Note:

① the state of a Job object becomes self-triggering when the time to allocate a job expires, not when all processes end.

② by default, when the job time expires, all its processes are automatically terminated, so the job_object_msg_end_of_job_timeis not delivered. If you just want to send the notification to the application and let the application kill the process by itself, you can do the following:

  // Create a struct and fill in the structure with the actions to take at the end of the JOb

jobobject_end_of_job_time_information joeojti;

Joeojti. Endofjobtimeaction = Job_object_post_at_end_of_job; // deliver notifications instead of "kill" the process. When the job is created, the default value is job_object_terminate_at_end_of_job;

 // tell the Job object what to take when the job time expires

setinformationjobobject (hjob,jobobjectendofjobtimeinformation,

&joeojti,sizeof (JOEOJTI));

"Jobio" uses completion ports for process management

5th Job and Process Pool (2)