Here is an excellent article written by Chris Nauroth on how to tune GC.

 

https://community.hortonworks.com/articles/14170/namenode-garbage-collection-configuration-best-pra.html

 

Here is another guide that explains the relative file objects size and GC settings.

 

https://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.4.2/bk_installing_manually_book/content/ref-80953924-1cbf-4655-9953-1e744290a6c3.1.html

 

Since you mentioned pause as an issue, this might help you.

 

https://docs.hortonworks.com/HDPDocuments/Ambari-2.2.2.0/bk_Ambari_Users_Guide/content/_tuning_garbage_collection.html

 

--Anu

 

 

 

From: sandeep vura <sandeepvura@gmail.com>
Date: Tuesday, September 13, 2016 at 6:11 AM
To: "user@hadoop.apache.org" <user@hadoop.apache.org>
Subject: Pause duration alert on Name Node

 

Hi Hadoop experts,

 

We are getting continuous Pause duration alert from Standby NN. 

 

Current configuration for Java heap size of NN : 7.8 GB

 

When we checked NN webUI heap memory used 7.5 GB of 7.8 GB heap memory. 

 

Please suggest how to fix this.

 

Thanks

sandeep