Linux gets real-time in real time

By: Carsten Emde

High-resolution timers and the dynamic tick feature made it into mainline

Thomas Gleixner,
OSADL's kernel maintainer

After Linux 2.6.20 was released on the now famous Super Kernel Sunday, Linux kernel developers did not lean back or left for holidays. In contrast, the two-weeks interval between a kernel release and the occurrence of the first release candidate of the subsequent kernel version always is the most hectic and politically active period. During these days, the decision is made which features and fixes will be included into the next kernel version.

And here are the good news for all of us: Thomas Gleixner's and Ingo Molnar's high-resolution timers and dynamic tick features have been merged into Linus Torvalds's kernel tree. Up to now, these features were only available through separate patches. Every vanilla kernel from Linux 2.6.21 onward will have these features, if configured accordingly. This is an important step toward the fully realtime-capable vanilla Linux kernel. After the first parts of the "Realtime Preempt Patches" have been merged in August 2006 (2.6.18), and another large part has been merged now, there is little doubt that all important components of the "Realtime Preempt Patches" will be included into the vanilla kernel in the foreseeable future.

Thanks to Thomas Gleixner, Ingo Molnar and all the kernel developers world-wide who made this happen!