Linux Plumbers Conf 2009

The scheduler tick must die. The kernel has long had a “tickless” or “nohz” mechanism to shut down the timer tick when not needed, but this mechanism only works when idle, not when running. If every function currently polling from the timer tick could instead make use of an appropriate event, or just wait to get updated until the next time the kernel has work to do, the kernel could become entirely event-driven. An event-driven kernel would improve throughput by decreasing interruptions, improve latency by removing large non-preemptible regions, improve consistency by eliminating the primary source of jitter, and improve power savings by getting done and back to sleep sooner.

We take an in-depth look at two kinds of startup procedures: the initramfs system, and the process of loading and executing ELF binaries.

We aim to inform you about the archive formats you use every day. We will include an in-depth look at the tar, ar, cpio, gzip, bzip2, and deb formats, as well as the internals of the Git object store. Armed with this information, we will show you a practical application: removing the redundancy between files in version control and distributions of source and binaries.

I present a new algorithm for scalable concurrent hash tables, performance results for this algorithm (2-10x more scalable than Linux), and potential applications.

Co-conspirators Jamey Sharp and Josh Triplett get up to a lot of miscellaneous hacking mischief together. Much of this hacking occurs while staring at the same screen, and tag-teaming the keyboard. Sometimes this happens with the two of them in different places. Learn how we manage this and why it's awesome.