The software described in this documentation is either in Extended Support or Sustaining Support. See https://www.oracle.com/us/support/library/enterprise-linux-support-policies-069172.pdf for more information.
Oracle recommends that you upgrade the software described by this documentation as soon as possible.

2.2 Recommended Strategy

Oracle Linux ships with hundreds of popular Linux utilities and tools. Many popular GNU utilities, libraries, and applications are available as optional installable packages and can be installed based on specific application requirements. For example, scripting languages such as gnu-coreutils, gnu-findutils, binutils, glib2, gtk2, Perl, Bison, Ruby, Python, and PHP, as well as Tcl/Tk libraries, GNU Emacs, Apache HTTP server, the GCC compiler, and many other development tools are available.

For the migration phases, you should estimate the time required for completing the tasks. The amount of effort required does not usually depend on the target platform. For example, the times required for functional, soak, and stress testing are usually fairly consistent across platforms. The area that potentially poses the maximum uncertainly is the complexities that are involved in porting the code. This uncertainty can be minimized by spending sufficient time and effort during the planning phase.

Although the source and target operating systems might be similar in many aspects, you might observe subtle differences when it comes to porting. Hence, the effort required for the transition to Oracle Linux can vary greatly due to the composition of application components as well as the programming language and tools that the various application subcomponents use. To arrive at an estimate for the porting effort, it is important to classify the various application subcomponents based on their implementation complexities.