Re: Discussion at Linux Foundation Japan Symposium

[KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>]

Hi!

> Hi all,
> 
> Long time no see and sorry for my late report.
> 
> I attended 9th Linux Foundation Japan Symposium and 
> discussed on issues of systemtap project with Ted Ts'o, 
> James Bottomley and Jonathan Corbet.
> 
> In my understanding, they demand the following things:

Great!


> (1) Follow upstream first
> 
> Utrace and uprobe features are currently available only 
> on Fedora and Red Hat Enterprise Linux, since those 
> patches are not merged into upstream kernel yet.
> 
> my suggestion:
> 
> To reduce complaints of upstream kernel developers, 
> systemtap project may need to postpone adding new 
> uprobe features until getting utrace (and uprobe) 
> patch set accepted in mainline.

Sure!

> (2) Maintain tapset
> 
> Systemtap users (including kernel developers) get 
> frustrated because tapsets often do not work on 
> the latest kernel. Moreover, sometimes users 
> have to fix the tapset incompatibility of kernels.
> 
> my suggestion:
> 
> If systemtap procjet can fix this kind of incompatibilities
> within a few hours or days as Myths about systemtap 
> on the wiki claims, releasing new systemtap minor release
> tarball for each upstream kernel release would help users.

In recently lttng discusstion, Andrew Morton sugessted to don't only
merge lttng kernel part, but also merge userland tool.

I think SystemTap also can try above approach. it is happy for
mainline kernel developer.

Honestly, current SystemTap can't use so easily for mainline kernel
developer.
at least, I tried it in this year five times. but all challenge is fail ;-)

I wonder why systemtap doesn't merge any part into mainline.
At least, systemtap runtime depend on kernel interface largely.
merging is better, imho.


Otherwise, lkml developer (include other tracing developer, e.g. mathieu, steven)
don't understand systemtap design and requirement correctly.


Thanks!