[Devel] Re: [PATCH] pid: improved namespaced iteration over processes list

[Eric W. Biederman]

Sukadev Bhattiprolu <sukadev at linux.vnet.ibm.com> writes:

> The obvious trade-off is with systems that don't use containers which
> are porbably the majority at present. For them next_task() now becomes
> more expensive (instead of a simply going to next item on list, they have
> lookup in the pidmap, a lookup in  pid hash table followed by mapping the
> pid back to task). I think there was a discussion once on this and the
> conclusion was things like "kill sig -1" are inherently expensive.

Cost wise it would be worth measuring.  I have a report that when that
change was made to /proc readdir in /proc sped up.

The problem that I see is that changing generic methods is not generally
applicable.

> Do you need these to be optimized for containers for some other reason ?

A good question.

Eric

_______________________________________________
Containers mailing list
Containers at lists.linux-foundation.org
https://lists.linux-foundation.org/mailman/listinfo/containers