Re: [PATCH V3 9/9] tracing: Add timerlat tracer

[Steven Rostedt]

On Sat, 12 Jun 2021 11:41:41 +0200
Daniel Bristot de Oliveira <bristot@xxxxxxxxxx> wrote:
> > I think the above may be easier to understand, especially if the trace
> > output that represents it is below.  
> 
> ok, I can try to capture a trace sample and represent it into the ASCII art
> format above.

Why capture it? Just fudge an example that fits the example ;-)

> 
> > Also, I have to ask, shouldn't the "thread noise" really start at the
> > "External clock event"?  
> 
> To go in that direction, we need to track things that delayed the IRQ execution.

[snip long explanation of the obvious (to me at least) ;-) ]

> the overhead is acceptable because of the sound analysis of the scheduling bound
> (which is rooted in a formal specification & analysis of the system).

I meant, that it needs to be documented, what the real thread noise is
but due to what is available it may not be truly accurate.

-- Steve