Last week I was working on a project where I need to schedule same Jobs for multiple clients at different time interval. I crated a Job class and scheduled it at different cron expression. But to my surprise when I triggered two job at same time only one of them get executed and to make it worse it was random. Sometime, job 1 gets executed sometime job2 get executed. Then after a lot of debugging i found that quartz fire an event and how many jobs can be executed for that even is determined by a parameter org.quartz.scheduler.batchTriggerAcquisitionMaxCount This tell that how many jobs can be scheduled when its triggered at same instance.