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

[Ingo Molnar]

* Frank Ch. Eigler <fche@xxxxxxxxxx> wrote:

> > Why are your despatching overheads 1000 cycles ? (and if its due to 
> > int3 why are you using int 3 8))
> 
> Smart teams from IBM and Hitachi have been hammering away at this code 
> for a year or two now, and yet (roughly) here we are.  There have been 
> experiments involving plopping branches instead of int3's at probe 
> locations, but this is self-modifying code involving multiple 
> instructions, and appears to be tricky on SMP/preempt boxes.

i am talking to them about that, and i'm 100% sure the solution is much 
easier than the many (much harder) problems that SystemTap has already 
solved. I think you are way too modest to realize how powerful (and 
important) SystemTap is :-)

	Ingo
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