Re: kernel summit session on systemtap

["R. J. Moore" <rasman at uk dot ibm dot com>]

Theodore Tso wrote:
> I spent about a couple of hours trying to get kdump to work on my
> laptop, and then gave up.  That's another RAS tool which has mostly
> ignored by the kernel development community, and deployability and
> usability has been one of its problems...
>
>   
Never had a problem with kdump, so your comment surprises me. Have you 
documented your issues?

> > I admit that this is extreme debugging,  
> > but if system tap won't even operate without a ton of extra junk present  
> > then I see its application as being very limited indeed.   Not everyone  
> > will want to work at the assembler level, but if System Tap can, then  
> > tools can be built that do code analysis to help generate and divine  
> > probepoints. Much can be done knowing that nearly 100% of the code we  
> > probe is generated by the one tool - gcc. In theory, what is generated  
> > is deterministic, or the reverse engineering of it is.
> >     
>
> My guess is that right now, the level 3 debugging experts at places
> like Red Hat, IBM, Novell, etc., are the only people who find
> SystemTap useful.  The quick survey done at the kernel summit pretty
> conclusively showed that most kernel developers haven't tried to use
> it, ....

Why should you expect this (or kdump) to be solely for kernel 
developers? Its for debuggers, which may or may not be the same set of 
folks. And those who concern themselves with complex live scenarios are 
often not the same folks - at least not willingly so. This tired old 
view that stipulates all that goes on in a kernel is for an exclusive 
clique of kernel developers is a nonsense.


Richard


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Richard J Moore
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