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

Andrew Morton
2006-06-09T23:54:06Z

Jay Lan <jlan@engr.sgi.com> wrote:
>
> Is a system-wide switch that bad?

Yes, it's awful. OK, we might band-aid something like that onto an
existing feature which had compatibility requirements, but for brand-new
code, no. Let's get it right.

> A site that needs tgid stats can live
> with the performance consequence while those do not need tgid can
> enjoy a pure per-task stats data. (I would argue that a thread group
> is some sort of task aggregate.)

But the performance impact was negligible. A few percent on a workload
which just sat in a fork/exit busyloop.

> How about sending tgid stats when the last process in the group exist?
> But do not send it if not the last in the thread?

That'd be one for Balbir to think about.