Re: [PATCH 0/11] LTTng-core (basic tracing infrastructure) 0.5.108

Roman Zippel
2006-09-14T21:02:47Z

Hi,

On Thu, 14 Sep 2006, Ingo Molnar wrote:

> > It's only zero maintenance overhead for you. Someone has to maintain
> > it. The party line for years has been that in-tree maintenance is
> > easier than out-of-tree maintenance.
>
> There's a third option, and that's the one i'm advocating: adding the
> tracepoint rules to the kernel, but in a _detached_ form from the actual
> source code.
>
> yes, someone has to maintain it, but that will be a detached effort, on
> a low-frequency as-needed basis. It doesnt slow down or hinder
> high-frequency fast prototyping work, it does not impact the source code
> visually, and it does not make reading the code harder. Furthermore,
> while a single broken LTT tracepoint prevents the kernel from building
> at all, a single broken dynamic rule just wont be inserted into the
> kernel. All the other rules are still very much intact.

This pretty much contradicts existing experience, most core events are
rather static - a schedule event is a schedule event no matter how the
actual scheduler is implemented.
Separate tracepoints are like separate documentation, there are forgotten
by the developers who could easily keep them uptodate if they were close
to the source.

bye, Roman