This section needs a lot more info on how to set up a LL kernel, how to write apps for it... maybe just link to Benno's old instructions? Anyone care to re-write this page?
Before version 2.4, the linux kernel provided pretty bad latency performance. It was almost guaranteed that something would cause problems unless you had huge audio buffers, which made the system very clunky for doing interactive realtime work; we usually resorted to the kind of hacks listed on the OldDropoutTips section.
Ingo Molnar came along and created some patches to the Linux 2.0 series, later ported to 2.2, which improved this dramatically. He got latency results under 3 milliseconds from input to output. This is, quite frankly, amazing for a general-purpose operating system like Linux; only BeOS? (designed for multimedia) had claimed such figures before. The other alternatives are "hard realtime" operating systems such as RTLinux, which are much harder to develop applications for, and (most of us feel) overkill for what we need.
Andrew Morton then tried to create a simpler, more elegant patch. He was successful; his results are close to Ingo's and the patch is a lot smaller.
Low latency patches (and benchmarks) vs kernel 2.2 are here. kernel 2.4 lowlatency patches can be found here.
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