title: Quartz.Net jobs not always running - can't find any reason why
body: <p>We're using Quartz.Net to schedule about two hundred repeating jobs.  Each job uses the same IJob implementing class, but they can have different schedules.  In practice, they end up having the same schedule, so we have about two hundred job details, each with their own (identical) repeating/simple trigger, scheduled.  The interval is one hour.</p>
  
  <p>The task this job performs is to download an rss feed, and then download all of the media files linked to in the rss feed.  Prior to downloading, it wipes the directory where it is going to place the files.  A single run of a job takes anywhere from a couple seconds to a dozen seconds (occasionally more).</p>
  
  <p>Our method of scheduling is to call GetScheduler() on a new StdSchedulerFactory (all jobs are scheduled at once into the same IScheduler instance).  We follow the scheduling with an immediate Start().</p>
  
  <p>The jobs appear to run fine, but upon closer inspection we are seeing that a minority of the jobs occasionally - or almost never - run.</p>
  
  <p>So, for example, all two hundred jobs should have run at 6:40 pm this evening.  Most of them did.  But a handful did not.  I determine this by looking at the file timestamps, which should certainly be updated if the job runs (because it deletes and redownloads the file).</p>
  
  <p>I've enabled Quartz.Net logging, and added quite a few logging statements to our code as well.  </p>
  
  <p>I get log messages that indicate Quartz is creating and executing jobs for roughly one minute after the round of jobs starts. </p>
  
  <p>After that, all activity stops.  No jobs run, no log messages are created.  Zero. </p>
  
  <p>And then, at the next firing interval, Quartz starts up again and my log files update, and various files start downloading.  But - it certainly appears like some JobDetail instances never make it to the head of the line (so to speak) or do so very infrequently.  Over the entire weekend, some jobs appeared to update quite frequently, and recently, and others had not updated a single time since starting the process on Friday (it runs in a Windows Service shell, btw).</p>
  
  <p>So ... I'm hoping someone can help me understand this behavior of Quartz.  </p>
  
  <p>I need to be certain that every job runs.  If it's trigger is missed, I need Quartz to run it as soon as possible.  From reading the documentation, I thought this would be the default behavior - for SimpleTrigger with an indefinite repeat count it would reschedule the job for immediate execution if the trigger window was missed.  This doesn't seem to be the case.  Is there any way I can determine why Quartz is not firing these jobs?  I am logging at the trace level and they just simply aren't there.  It creates and executes an awful lot of jobs, but if I notice one missing - all I can find is that it ran it the last time (for example, sometimes it hasn't run for hours or days).  Nothing about why it was skipped (I expected Quartz to log <em>something</em> if it skips a job for any reason), etc.</p>
  
  <p>Any help would really, really be appreciated - I've spent my entire day trying to figure this out.</p>