Issue with Quartz grail plugin - grails

Question

I have a grails application and a quartz job running on it. The job contains the below code similar to below .
class MyJob{
static triggers = {}
def printLog(msg){
String threadId = Thread.currentThread().getId()
String threadName = Thread.currentThread().getName()
log.info(threadId+" - "+threadName+" : "+msg)
}
def execute(context)
{
printLog("Before Sync");
synchronized(MyJob){
printLog("Inside Sync");
try{
printLog("Before sleep 20 minutes")
Thread.sleep(1200000)
printLog("After sleep")
}catch (Exception e){
log.error("Error while sleeping")
}
}
printLog("After Sync")
}
}
I have scheduled it to trigger a job every minute
I can see in the logs that one thread is getting the synchronized block and then the other jobs start piling up, waiting for the thread to finish, this is working as expected.
The issue here is the jobs stop after 10 minutes by that time it have created 10 Threads. Out of that one is sleeping for 20 minutes and other 9 are waiting for the 1st thread to release the lock. Why is no new jobs created ?
I saw in some answers I can fix the issue by modifying my triggers section like below
static triggers = {
simple repeatInterval: 100
}
I tried the above option and its still showing only 10 jobs.
From where its taking the default configuration of 10 ?
How can i modify the value to do infinitely ?
I am new to grails and quartz, so I have no idea what is happening.

Answer 1

I think the Grails plugin sets the threadCount to 10 in the bundled quartz.properties file, assuming you're using Grails 3 you can override in application.yml like this:
quartz:
threadPool:
threadCount: 25
Grails 2 - application.groovy
quartz {
props {
threadPool.threadCount = 100
}
}

Answer 2

In general, it's not a a good idea to lock the Job thread with sleeps
If you have a job running a long process you must to split it in several jobs in order to release the Thread as soon as posible