The UEK kernel is a way for Oracle to provide an updated set of capabilities in Linux beyond what Red Hat packages in Red Hat Enterprise Linux (RHEL). Oracle Linux is based on RHEL, but that doesn’t mean that it needs to be limited by it either.
Wim Coekaerts, senior vice president, Linux and Virtualization Engineering at Oracle, explained that Oracle tracks the mainline Linux kernels closely. The last major update of UEK was UEK 2, which debuted back in March of 2012.
Coekaerts explained that the timeline for UEK is for new releases every 18 months. UEK Release 1 was based on the 2.6.32 kernel while the UEK Release 2.0 was based on the Linux 3.0 kernel.
The new UEK Release 3 is based on the Linux 3.8 kernel update that was first publicly released by Linus Torvalds earlier this year.