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Date: Wed, 26 Jun 2013 16:34:00 +0900
From: Minchan Kim <minchan@kernel.org>
Subject: Re: [PATCH v6] memcg: event control at vmpressure.
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To: Hyunhee Kim <hyunhee.kim@samsung.com>
Cc: Michal Hocko <mhocko@suse.cz>, Anton Vorontsov <anton@enomsg.org>, linux-mm@kvack.org, akpm@linux-foundation.org, rob@landley.net, kamezawa.hiroyu@jp.fujitsu.com, hannes@cmpxchg.org, rientjes@google.com, kirill@shutemov.name, Kyungmin Park <kyungmin.park@samsung.com>

On Sat, Jun 22, 2013 at 01:51:17PM +0900, Hyunhee Kim wrote:
> And one more thing.
> 
> vmpressure sends all of the lower events than the level (current).
> 
> 155         list_for_each_entry(ev, &vmpr->events, node) {
> 156                 if (level >= ev->level) {
> 157                         eventfd_signal(ev->efd, 1);
> 158                         signalled = true;
> 159                 }
> 160         }
> 
> Isn't it wasteful?
> When we registered "low" and "critical", and the current level is
> critical, why should we signal "low" level together?
> If we receive "critical" only, can't we just assume "low" level at the
> user space?

Agree.

-- 
Kind regards,
Minchan Kim

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