On Tue, 10 Jun 2025 11:43:43 +0200 Nam Cao <[email protected]> wrote:
> --- /dev/null > +++ b/Documentation/trace/rv/monitor_rtapp.rst > @@ -0,0 +1,116 @@ > +Real-time application monitors > +============================== > + > +- Name: rtapp > +- Type: container for multiple monitors > +- Author: Nam Cao <[email protected]> > + > +Description > +----------- > + > +Real-time applications may have design flaws such that they experience > unexpected latency and fail > +to meet their time requirements. Often, these flaws follow a few patterns: > + > + - Page faults: A real-time thread may access memory that does not have a > mapped physical backing > + or must first be copied (such as for copy-on-write). Thus a page fault > is raised and the kernel > + must first perform the expensive action. This causes significant delays > to the real-time thread > + - Priority inversion: A real-time thread blocks waiting for a > lower-priority thread. This causes > + the real-time thread to effectively take on the scheduling priority of > the lower-priority > + thread. For example, the real-time thread needs to access a shared > resource that is protected by > + a non-pi-mutex, but the mutex is currently owned by a non-real-time > thread. > + > +The `rtapp` monitor detects these patterns. It aids developers to identify > reasons for unexpected > +latency with real-time applications. It is a container of multiple > sub-monitors described in the > +following sections. > + Again, please limit the documentation to 80 columns. Thanks! -- Steve
