Re: [PATCH 1/3] taskstats-fork: Add a new taskstats command to get notification on fork/clone

Balbir Singh
2009-08-31T06:46:53Z

* Guillaume Chazarain <guichaz@gmail.com> [2009-08-30 21:52:22]:

> On Tue, Jul 21, 2009 at 8:24 AM, Nikanth Karthikesan<knikanth@suse.de> wrote:
> > Ah.. proc-events was the exact thing, I was looking for! Thanks.
>
> AFAICT proc-events can only be used by root, so that makes it
> unsuitable for *top.
>
> Anyway, iotop will always have to iterate over all threads to query
> their taskstats and other attributes, so the O(nr_threads) complexity
> is unavoidable.
>

Unless you want the stats for tgid in signal struct. In some cases we
accumulate, in some we don't. But yes irrespective or kernel/user
space the complexity exists.

--
Balbir