Scheduled Batch Apex Hangs in Queued Status

Question

This is my first crack at a scheduled batch Apex class. Copied the code from the manual but missing something. When I run class MassDeleteSchedules in Anonymous block, it works fine. But when I use the UI to schedule it it just hangs in queued status. I gave it a couple hours and nothing changed so cancelled it. There's only 1 batch that's being scheduled.

I feel like the last 2 lines are causing the issue.

global class JobScheduler implements Schedulable{
global void execute(SchedulableContext scMain){
    CronTrigger ct = [SELECT Id, CronExpression, TimesTriggered, NextFireTime
                      FROM CronTrigger WHERE Id = :scMain.getTriggerId()];

    System.debug(ct.CronExpression);
    System.debug('Number of times batch triggered '+ ct.TimesTriggered);

    //Ensure batch not already triggered
    System.assertEquals(0, ct.TimesTriggered);

    // Sets up query for time period to remove records
    Date dt = Date.today();
    dt = dt.addMonths(-1);
    String dateStr = String.valueOf(dt); // Passing as string for dynamic query below

    String e = 'ONE__Schedule__c';
    String f = 'ONE__Start_Date__c';
    String v = null;
    String q = 'Select id, name from ' + e + ' where ' + f + ' < ' + dateStr;

    MassDeleteRecords del = new MassDeleteRecords(q,e,f,v);       
    Id idbatch = Database.executeBatch(del,2000);
   }
 }

Answer 1

Scheduled Batch Apex jobs appears as Queued status in the Apex Jobs page until the time comes to execute the job (i.e. as per the time you scheduled it to run).

Could it be that you had scheduled it to run by your local clock but the Salesforce time is different and the Job was never actually due to start yet (and hence it will be correctly showing Queued status)?

I see you have put some debug code in the execute() method, did you ever see that in your debug logs? If not, I'd suggest that your Job never even started.

Answer 2

I've also seen this issue. I'm not sure if normal scheduled jobs do this, but it looks like there is a bug in the apex jobs monitor if the scheduled job is calling a batch job within it. The scheduled job actually runs, but it is just stuck in queue status in the apex jobs monitor.

I know my scheduled job is executing because I see the batch job being kicked off right after it. In addition, I am doing an update to a custom setting within the scheduled job and I see that the setting has actually been updated.

Here is additional information on the issue. There seems to be a workaround to it.

Answer 3

When you create a listview on the Apex jobs, Make sure you select Apex class = 'your batch class name'. Note: your schedulded class view always shows either Aborted or Queued