A constant refrain over the decades from database, high-performance computing (HPC), and real-time developers has been: "Can't you just get the kernel out of the way?". Recent developments in the Linux kernel are paving the way to just that ideal: Linux is there whenever you need it, but if you follow a few simple rules, it is completely out of your way when you don't need it.

This adaptive-idle approach will provide bare-metal multicore performance and scalability to databases as well as to HPC and real-time applications. However, it is at the same time able to improve energy efficiency for upcoming asymmetric multicore systems, allowing these systems to better support workloads with extreme peak-to-mean utilization ratios. This talk will describe how this feat is accomplished and how it may best be used.