This page is currently a stub. Please help expanding it!

Tuning your system for low latency

Get a real-time kernel

Quite a few people have reported good results with Generally, it's advisable to get the latest stable release: if a friend tells you 2.6.X is good, and by the time you download, 2.6.X.Y is out, go for that. Low-latency behaviour will very likely be identical for the same X, but you will also get some important recent security fixes. Same goes for the realtime patch release. Always get the latest - they usually get better, not worse.

See if your distribution has the in-kernel config list enabled: search for a file named /proc/config.gz. If it exists, unzip it to your kernel source tree and rename it to .config. It will contain the kernel configuration of your currently running kernel, which you can use as a base. Then proceed as described in the low latency howto at It's slightly out-of-date but mostly usable.

Once you've come this far, any question you might want to ask on the ffado-user list will almost certainly be an intelligent and interesting one. Please share youre experience and report problems.

Kernel scratchpad - please review and fix!

  • many people advise to use a tickless kernel for rt audio
  • many people advice CONFIG_HZ=1000. isn't that the "jiffies" thing, and isn't that very same thing made obsolete by a tickless system?
  • high-resolution timers are recommended for rt kernels. kernel docs say that hrtimers are independent of jiffies.

Tweak your IRQ priorities

IRQ priorities

Get rid of resource hogs

Shut down CPU or I/O intesive processes that might run in the background, such as

  • Desktop indexing tools like beagle
  • the mandb updater
    • Backup systems