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

Andrew Morton
2006-06-21T21:54:52Z

On Wed, 21 Jun 2006 14:45:01 -0700
Jay Lan <jlan@engr.sgi.com> wrote:

> > Won't it suffice to make delivery of these stats best effort, with
> > userspace dealing with missing data,
>
> How do you recover the missed data?

I suspect the best we can do is to let userspace know that data was lost.
Is the -ENOBUFS reliable?

> > rather than risk delaying exits ? The cases where exits are so
> > frequent as in this program should be
>
> This is very true. However, it was a 2p IA64 machine. I am too frightened to
> speak "512p"...

If we have 511 CPUs generating data faster than one CPU can handle it,
something bad will happen. We either throttle the 511 CPUs or drop data.