Re: init's children list is long and slows reaping children.

Robin Holt
2007-04-06T10:43:07Z

> So I think we have some options once we get the kernel threads out
> of the way. Getting the kernel threads out of the way would seem
> to be the first priority.

I think both avenues would probably be the right way to proceeed.
Getting kthreads to not be parented by init would be an opportunity
for optimization.

I think organizing the zombie tasks to be easily reaped also has merit.
Rapidly forking/exiting processes like udevd during the boot of a
different machine were also shown to benefit significantly from this
patch. That machine had 512 cpus and 4608 disk devices, we dropped the
device discovery under udevd by 30%. This, honestly, surprised us.
It makes some sense now that I think about it. This would be a case
where improving the zombie handling would be beneficial to more than
just kthreads.

Thanks,
Robin