We Are Not Getting Any Younger: A New Approach to Time and Timers

The Linux time subsystem, which once provided only tick granularity via a simple periodic addition to xtime, now must provide nanosecond resolution. As more and more unique timekeeping hardware becomes available, and as virtualization and low-latency demands grow, the complexity of maintenance and bug resolution increases.

We are proposing a significant re-work of the time keeping subsystem of the kernel. Additionally, we demonstrate some possible enhancements this re-work facilitates: a more flexible soft-timer subsystem and dynamic interrupt source management.

...

Download PDF.