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Date:   Thu, 11 Jun 2020 16:11:16 +0100
From:   Mel Gorman <mgorman@suse.de>
To:     Jaewon Kim <jaewon31.kim@samsung.com>
Cc:     Mel Gorman <mgorman@techsingularity.net>,
        Baoquan He <bhe@redhat.com>, minchan@kernel.org,
        hannes@cmpxchg.org, akpm@linux-foundation.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, jaewon31.kim@gmail.com,
        ytk.lee@samsung.com, cmlaika.kim@samsung.com
Subject: Re: [PATCH] page_alloc: consider highatomic reserve in wmartermark
 fast
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On Thu, Jun 11, 2020 at 10:43:20AM +0900, Jaewon Kim wrote:
> > That's fine, I simply wanted to illustrate where I thought the check
> > should go to minimise the impact to the majority of allocations.
> Hello Mel.
> Can I understand that you also agrees on checking highatomic reserved?
> 

Yes, I think it should be ok.

> Additionally I've wondered why the number of  highatomic free pages is not
> accurately counted like cma free. Is there any concern on counting it?

At the time, the cost of tracking it with 100% accuracy was not worth
it due to a reliance on the pageblock types to protect the regions from
other allocation types.

-- 
Mel Gorman
SUSE Labs