jobs not getting triggered at correct intervals

[JG00329142]

HI
I have 2 jobs with separate triggers,
trigger : group1.triggerA For Job key refreshgroup1.refreshjobA will run at: Tue Oct 18 15:23:12 IST 2016 and repeat: 10 times, every 10 seconds
trigger : group2.triggerB For Job key refreshgroup1.refreshjobB will run at: Tue Oct 18 15:23:14 IST 2016 and repeat: 10 times, every 7 seconds

But in the output i see that Job A doesnot repeat after 10 sec, Sometime the interval is 20 sec, sometimes it is 14 sec

Same problem for Job B. the interval is not 7 sec as it is configured to be. What am i missing here?

Thanks for your help.

------- Starting Scheduler ----------------
------- Started Scheduler -----------------
------- Waiting 90 seconds... -------------
RefreshJob: execute called Tue Oct 18 15:23:19 IST 2016 : for A
RefreshJob: execute called Tue Oct 18 15:23:26 IST 2016 : for B
RefreshJob: execute called Tue Oct 18 15:23:32 IST 2016 : for B
RefreshJob: execute called Tue Oct 18 15:23:39 IST 2016 : for A
RefreshJob: execute called Tue Oct 18 15:23:45 IST 2016 : for B
RefreshJob: execute called Tue Oct 18 15:23:52 IST 2016 : for A
RefreshJob: execute called Tue Oct 18 15:23:59 IST 2016 : for B
RefreshJob: execute called Tue Oct 18 15:24:06 IST 2016 : for A
RefreshJob: execute called Tue Oct 18 15:24:14 IST 2016 : for B
RefreshJob: execute called Tue Oct 18 15:24:21 IST 2016 : for B
RefreshJob: execute called Tue Oct 18 15:24:28 IST 2016 : for A
RefreshJob: execute called Tue Oct 18 15:24:35 IST 2016 : for B
RefreshJob: execute called Tue Oct 18 15:24:42 IST 2016 : for A