Re: [Patch][RFC] Disabling per-tgid stats on task exit in taskstats

[Andrew Morton <akpm@osdl.org>]

On Mon, 26 Jun 2006 14:00:45 -0400
Shailabh Nagar <nagar@watson.ibm.com> wrote:

> >
> >Balbir, are you able to summarise where we stand wrt
> >per-task-delay-accounting-* now?
> >  
> >
> Andrew,
> 
> I'm maintaining per-task delay accouting and taskstats interface patches 
> so I'll take the liberty to reply :-)

Sorry, too many IBMers ;)

> >What problem have we identified?  How close are we to finding agreeable
> >solutions to them?
> >  
> >
> The main problems identified are:
> 
> 1. extra sending of per-tgid stats on every thread exit
> 2. unnecessary send of per-tgid stats when there are no listeners
> 3. unnecessary linkage of delayacct accumalation into per-tgid stats 
> with sending out of taskstats
> 
> All three have an acceptable solution.
> 1. & 3. are going to be addressed in a patch I'm sending out shortly.
> 2. in a separate patch also being sent out shortly.

Great.

> >My general sense is that there's some rework needed, and that rework will
> >affect the userspace interfaces, which is a problem for a 2.6.18 merge.
> >  
> >
> The rework will affect the number of per-tgid records that userspace 
> sees (fewer), not the format or any of the
> other details regarding the genetlink interface.
> Will that be a problem for userspace ?

Nope.

OK, please send the patch and I'll plan on sending this lot to Linus
Thursdayish.