Re: Discussion at Linux Foundation Japan Symposium

[William Cohen <wcohen@redhat.com>]

Frank Ch. Eigler wrote:
> Hi -
> 
> On Fri, Dec 19, 2008 at 08:58:58AM +0900, KOSAKI Motohiro wrote:
>>>> Systemtap always requires kernel debuginfo to use.  Unfortunately,
>>>> it is hard for users of some distributions to have debuginfo.
>>> Those distributions ought to be lobbied to improve this situation,
>>> since there are many non-systemtap uses of debugging data - such as
>>> debuggers, kernel- and user-space crash dump analysis tools.
>> [...]
>> In enterprise usage, crash dump analysis is provided by vendor.
>> but tapset run on customer. [...]
> 
> That is just one scenario.  Another compelling use for debuginfo is a
> tool like oprofile.
> 
> - FChE

For the case where oprofile data is being mapped back to lines in the source 
code debuginfo is needed. However, for the case just want to know which 
functions the code is spending time in oprofile doesn't use debugging 
information produced by -g; it just looks for the function locations in the 
code.  Unfortunately, the strip operations used for binaries in distribution 
strip out all information from the binary leaving just the minimal executable 
bits, making the debuginfo the only place to get that information.

It would be nice if there was something between the extremes of a huge amount of 
information in the debuginfo or nothing at all.


-Will