Quartz.net durable and clustered - quartz.net

Question

The config:
<quartz>
<add key="quartz.scheduler.instanceName" value="ChengongDemo" />
<add key="quartz.scheduler.instanceId" value="AUTO" />
<!--线程池-->
<add key="quartz.threadPool.type" value="Quartz.Simpl.SimpleThreadPool, Quartz" />
<add key="quartz.threadPool.threadCount" value="5" />
<add key="quartz.threadPool.threadPriority" value="Normal" />
<add key="quartz.jobStore.type" value="Quartz.Impl.AdoJobStore.JobStoreTX, Quartz" />
<add key="quartz.jobStore.tablePrefix" value="QRTZ_" />
<add key="quartz.jobStore.driverDelegateType" value="Quartz.Impl.AdoJobStore.SqlServerDelegate, Quartz" />
<add key="quartz.jobStore.dataSource" value="myDb" />
<add key="quartz.dataSource.myDb.connectionString" value="Data Source=192.168.15.23;Initial Catalog=Quartz;User ID=sa;Password=123456789" />
<add key="quartz.dataSource.myDb.provider" value="SqlServer-20" />
<!-- 集群-->
<add key="quartz.jobStore.Clustered" value="true" />
<add key="quartz.jobStore.clusterCheckinInterval" value="600" />
</quartz>
The code:
public static void Run()
{
ISchedulerFactory sf = new StdSchedulerFactory();
Sched = sf.GetScheduler();
var jobDetail = new JobKey("job1", "group1");
var triggerKey = new TriggerKey("trigger1", "group1");
if (!Sched.CheckExists(jobDetail) && !Sched.CheckExists(jobDetail))
{
var job = JobBuilder.Creaenter code herete<TestJob>()
.WithIdentity(jobDetail)
.Build();
var trigger = TriggerBuilder.Create()
.WithIdentity(triggerKey)
.ForJob(job.Key)
.WithCronSchedule("*/2 * * ? * *")
.Build();
Sched.ScheduleJob(job, trigger);
}
Sched.Start();
}
The Result:
enter image description here
The service run normally. I shundown for a few seconds,Then I start again.The
Job ran several times at the same time.
Why？Someone can help me?Thank you for your help.

Answer 1

If you want to disallow "running at the same time", then apply the
DisallowConcurrentExecution
attribute
https://www.quartz-scheduler.net/documentation/quartz-2.x/tutorial/more-about-jobs.html
As in
[DisallowConcurrentExecution]
public class MyDoesNotRunConcurrentlyJob : IJob
{
HOWEVER, I think what you are experiencing is your first experience with a "misire" , or a job didn't execute on the utopia schedule....then there are rules around that.
I would read the below URL. While its for the java-quartz (and quartz.net is a "port over" (to .net), the below is the best mini resource for understanding misfires.
he even mentions your specific case
"the scheduler itself was down"
http://www.nurkiewicz.com/2012/04/quartz-scheduler-misfire-instructions.html
I will copy the header information here, in case the url ever "dies", you (or more likely future readers) can use the below text to search for the article.
Quartz scheduler misfire instructions explained
Sometimes Quartz is not capable of running your job at the time when you desired. There are three reasons for that:
all worker threads were busy running other jobs (probably with higher priority)
the scheduler itself was down
the job was scheduled with start time in the past (probably a coding error)