Page History

Table of Contents

	outlinh1. true
	outlinh1. true
1	printablefalse
2	stylh1. none
3	indent20px

Scope

The functions for terminating task processes

...

for the JobScheduler Master and Universal Agent have been extended to allow the use of both SIGTERM and SIGKILL signals on Unix servers

...

:
- SIGTERM is sent first and allows an orderly

...

- termination of task processes to take place

...

- within a limited period of time.
- If the time allowed has been exceeded and the processes are still running then SIGKILL will be sent.
The information contained in this article draws together detailed information contained in a range of issues and should primarily be of interest to persons in engineering and to a lesser extent persons in operating functions.

Feature History

This feature has been implemented stepwise between Release 1.9.0 and 1.10.0 (see the table of issues below for more detailed information).

Display feature availability

StartingFromRelease	1.9

Related Issues

Support of this feature is subject to the following issues:features:

Jira
server SOS JIRA
columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution
serverId 6dc67751-9d67-34cd-985b-194a8cdc9602
key JS-1495
Jira
server SOS JIRA
columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution
serverId 6dc67751-9d67-34cd-985b-194a8cdc9602
key JS-1468
Jira
server SOS JIRA
columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution
serverId 6dc67751-9d67-34cd-985b-194a8cdc9602
key JS-1463
Jira
server SOS JIRA
columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution

...

serverId 6dc67751-9d67-34cd-985b-194a8cdc9602
key JS-1421
Jira
server SOS JIRA
columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution
serverId 6dc67751-9d67-34cd-985b-194a8cdc9602
key JS-1420
Jira
server SOS JIRA
columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution
serverId 6dc67751-9d67-34cd-985b-194a8cdc9602
key JS-1382
Jira
server SOS JIRA
columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution
serverId 6dc67751-9d67-34cd-985b-194a8cdc9602
key JS-1307
Jira
server SOS JIRA
columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution
serverId 6dc67751-9d67-34cd-985b-194a8cdc9602
key JS-1163
Jira
server SOS JIRA
columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution

...

serverId 6dc67751-9d67-34cd-985b-194a8cdc9602
key JOC-10

Use Case

The information contained in this article draws together detailed information contained in a range of issues and should primarily be of interest to persons in engineering and to a lesser extent persons in operating functions.

Implementation

Users who schedule programs and scripts that are aware of SIGTERM signals can implement clean-up procedures on receipt of the signal. Clean-up includes e.g. removal of temporary files, disconnect from a database and similar tasks.

The use of both SIGTERM and SIGKILL signals on Unix servers has the following advantages:
- The use of SIGTERM before SIGKILL means that there is a greater chance of data being saved after after the the kill command signal has been issued.
- The SIGTERM signal can - in contrast with SIGKILL - be monitored, i.e. a prepost-/postprocessing processing Script can be carried out. This means that the ending of a task by the JobScheduler can be reacted to and the sudo user process itself can be ended.
- The post-processing methods implementation of SIGTERM allows post-processing methods such as spooler_process_after to complete within the timeout period().
The time allowed between the SIGTERM and the SIGKILL signals can be specified in the command using the timeout attribute (the default is 15 sec) - : <kill_task … timeout=".."/>
This feature can also be applied for:
- remote processes - , i.e. processes started by SSH and those started by an agentAgent,
- child processes started by a process running on an agent (
  Jira
  server SOS JIRA
  columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution
  serverId 6dc67751-9d67-34cd-985b-194a8cdc9602
  key JS-1468
  ).

Implementation

JobScheduler

...

Master

The following operations can be carried out from the JobScheduler Operating Center interface (JOC) or by use of the command line:

Operation: kill immediately
- JOC sends <kill_task immediately="yes"/>
- The process is killed immediately using the SIGKILL signal.
Operation: terminate with timeout
- JOC sends <kill_task immediately="yes" timeout="15"/>
- The process receives a SIGTERM signal. Should that process not terminate within the specified timeout period then it will be killed with a SIGKILL signal.
Operation: terminate
- JOC sends <kill_task immediately="yes" timeout="never"/>
- The process receives a SIGTERM signal. Monitoring of the process termination as described in Operation 2 above is not carried out.

JobScheduler Universal Agent (JUA)

The JobScheduler Universal Agent uses a script to monitor and kill parent and child tasks.

The script is to be found the ./bin folder of the JUA installation.

The -kill-script option can be used to specify a different kill script if necessary. See the Command Line Options section in JobScheduler Universal Agent - Installation & Operation for more information.

Delimitation

This feature is intended for Unix platforms that implement the SIGTERM and SIGKILL signals. It is not intended for Windows platforms for which exclusively the Kill kill Immediately command applies.
When using traps then please consider that the process created by the <shell> the <script ... language="shell"/> element receives the signal. Subsequent scripts that are called within the <shell> <script ... language="shell"/> element will not receive the signal.
You could therefore:
- configure traps directly within the <shell> <script ... language="shell"/> element. The shell process will then receive and handle the signal.
- configure traps in a shell script that is added by an <include> element instead of being stated within the <shell> the <script ... language="shell"/> element. The included shell script will receive and handle the signal.
- forward signals to subsequent shell scripts that are called within a <shell> <script ... language="shell"/> element.

This feature has been fully implemented on for the Universal Agent . It has been implemented for classic and for the Classic JobScheduler Agents using TCP ((
Jira
server SOS JIRA
columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution
serverId 6dc67751-9d67-34cd-985b-194a8cdc9602
key JS-1420
).

Workaround

A monitor (i.e. a pre-/postprocessing script) has to be configured for shell jobs that have a timeout set (JS-1463).
For example:

Code Block

language	xml
title	Workaround for shell jobs with a timeout

<job name="shell_with_javascript_monitor">
    <script  language="shell">
        <![CDATA[
echo hello world!
sleep 45
        ]]>
    </script>

    <monitor  name="process0" ordering="0">
        <script  language="java:javascript">
            <![CDATA[
function spooler_process_before(){
	return true;
}
            ]]>
        </script>
    </monitor>

    <run_time />
</job>

Implementation Summary

The implementation of the different termination operations available for the JobScheduler Master and Universal Agent is summarized in the table below.

The links lead to the issues relevant to the implementation of the feature.

The termination operations available are:

Terminate: <kill_task immediately="true" timeout="...">
Kill: <kill_task immediately="true">
Timeout: a job with the timeout attribute.

	Windows Standalone	Linux Standalone	Windows Classic Agent	Linux Classic Agent	Windows Universal Agent	Linux Universal Agent
Shell job
Terminate	not supported		not supported	JS-1420	not supported
Kill				JS-1421	JS-1468	JS-1468
Timeout	JS-1463	JS-1463				JS-1468
Shell job with monitor
Terminate	not supported		not supported		not supported	JS-1468
Kill					JS-1382	JS-1468
Timeout						JS-1382
API job
Terminate	not supported		not supported		not supported
Kill
Timeout

Task Termination in JOC

The following screenshot shows how a task can be terminated using the Task menu in JOC's Task pane. This pane is shown in the Jobs tab when the task is running and the task can be terminated either with timeout or immediately.

Image Added

Examples

Using a SIGTERM trap to show the difference between the `kill` and `terminate` commands

...

Download the Example

job_trap_sigterm.job.xml.zip

...

This example contains a job that uses a sigterm SIGTERM trap to show the difference between the kill<kill_task task> and terminate<terminate_task task> commands provided by JOC.

...

Start the job
Terminate the task in JOC
You will see the log message: sigterm will be ignored
The task will continue

Code Block

language	xml

<?xml version="1.0" encoding="ISO-8859-1"?>

<job  title="test test">
    <script  language="shell">
        <![CDATA[
trap 'echo sigterm will be ignored' 15
for i in 1 2 3 4 5 6 7 8 9 0
do
date
sleep 10
done
sleep 60
        ]]>
    </script>

    <run_time />
</job>

Change Management References

Jira

server	SOS JIRA
columns	type,key,issuelinks,fixversions,status,priority,summary,updated
maximumIssues	20
jqlQuery	labels in (terminate-tasks)
serverId	6dc67751-9d67-34cd-985b-194a8cdc9602

References

JobScheduler Reference Documentation:
- the <kill_task> XML command

...

Space shortcuts

Page tree

Versions Compared

Old Version 6

New Version Current

Key

Scope

Feature History

Related Issues

Use Case

Implementation

Implementation

JobScheduler

Master

JobScheduler Universal Agent (JUA)

Delimitation

Workaround

Implementation Summary

Task Termination in JOC

Examples

Using a SIGTERM trap to show the difference between the `kill` and `terminate` commands

Download the Example

Change Management References

References

Space shortcuts

Page tree

Page History

Versions Compared

Old Version 6

New Version Current

Key

Scope

Feature History

Related Issues

Use Case

Implementation

Implementation

JobScheduler

Master

JobScheduler Universal Agent (JUA)

Delimitation

Workaround

Implementation Summary

Task Termination in JOC

Examples

Using a SIGTERM trap to show the difference between the kill and terminate commands

Download the Example

Change Management References

References

Using a SIGTERM trap to show the difference between the `kill` and `terminate` commands