Thursday 28 January 2016

Performance issue when multiple users trying to login into Oracle EBS 12.1 at the same time.



Performance issue when multiple users trying to  login into Oracle EBS 12.1 at the same time:


Oracle EBS 12.1
Oracle Database 11.2.0.4


Problem Statement:

Multiple users trying to Login to Oracle Apps at same time , ie, when one of the Global Business Unit Comes online.
Most of the connections hangs doing nothing. For those who are already logged in , the forms navigation is extremely slow.


Resolution:

-        The performance problem is related with the fact that a lot of users are connecting at the same time and some connections get hung for some minutes doing nothing,
it could be due to the fact that oracle 11g jdbc driver is hanging/blocked by /dev/random ,ie, entropy pool empty.  

Usually Forms keeps a pool of jdbc connections.If more connections are needed, it needs to create new connections, and sometimes JDBC takes some time to create the connections because of the /dev/random problem.


The below is the solution:

-        -Create soft link : change in linux /dev/random to be a link to /dev/urandom.  
         This will be in effect till the server is rebooted.
       

  To make the changes  permanent :

In context files, adding  the following in all the jvm_start_options (forms, oacore, oafm):


-Djava.security.egd=file:/dev/./urandom

And run autoconfig.



Note: Entropy is the random things generated by a computer and used by Linux to generate random numbers. Linux uses the key strokes by an user to generate entropy and the entropy generates the random numbers in /dev/random.



Tuesday 5 January 2016

Upgrade Oracle Enterprise Manager 12.1.0.5 to 13.1

Upgrade Oracle Enterprise Manager 12.1.0.5 to 13c.


1) Apply the latest PSU to the Repository 12.1.0.2.0 Database.

2) Download zips and install script to the Management Server.

3) Run an one system upgrade .


DONE !!!!!!!


Reference Documentation: http://docs.oracle.com/cd/E63000_01/EMUPG/toc.htm