Cluster doesn't respond

I have submitted a simple wordcount job, the cluster is taking very long and not responding
job details

http://ip-172-31-35-141.ec2.internal:8088/proxy/application_1534581202967_0109/

Job was submitted 1 hour ago and it’s still in accepted sate. is there any problem with the cluster?

Hi @NB_NB,

We are in the process of optimizing server meomory. Can you please check now?

It was good after couple of hours. Thank you