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To: Vasily Averin <vvs@virtuozzo.com>
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Subject: Re: slabinfo shows incorrect active_objs ???
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On Thu, 24 Feb 2022, Vasily Averin wrote:

> > I assume for reduced overhead the counters would be implemented in a percpu
> > fashion as e.g. vmstats. Slabinfo gathering would thus have to e.g. sum up
> > those percpu counters.
>
> I like this idea too and I'm going to spend some time for its implementation.

Well vmstats are also not entirely accurate. Maintaining counters is
expensive and it gets more expensive if you want to always be accurate.

VM stats were created in order to decrease the overhead of counter
maintenance and the explicit aim was to sacrifice accuracy for
performance.