Re: Discussion at Linux Foundation Japan Symposium

["K.Prasad" <prasad@linux.vnet.ibm.com>]

On Thu, Dec 18, 2008 at 06:27:32PM +0900, KOSAKI Motohiro wrote:
> > > (3) Make no debuginfo version
> > >
> > > Systemtap always requires kernel debuginfo to use.
> > > Unfortunately, it is hard for users of some distributions
> > > to have debuginfo.
> > >
> > 
> > How is it possible to do that without kernel debug info? Currently
> > systemtap extracts lots of information on kernel layout from debug
> > info, so I dont understand why we can survive without that.
> 
> At least, dtrace don't need debuginfo.
> On Solaris 10, kernel and all executable binary have own tracing purpose
> information in special elf section.
> it can't be stripped and gurantee exist although product application binary.
> 
> http://blogs.sun.com/ali/entry/what_is_sunw_ldynsym
> 
> 
> Of cource, this approach indicate systemtap lost some feature.
> (e.g. above section don't have line number information and local
>  variable name information)
> 
> but it is still useful for average tracing user.
>
I'm not sure if the issue is discussed without being aware of the
dwarfless probing that's available in SystemTap since a while ago. More
details at: http://sourceware.org/systemtap/wiki/MakeDoWithoutDebugInfo

Thanks,
K.Prasad