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Date:   Thu, 26 Nov 2020 15:55:53 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Vlastimil Babka <vbabka@suse.cz>
Cc:     Yu Zhao <yuzhao@google.com>, Alex Shi <alex.shi@linux.alibaba.com>,
        Konstantin Khlebnikov <koct9i@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Hugh Dickins <hughd@google.com>,
        Michal Hocko <mhocko@suse.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH next] mm/swap.c: reduce lock contention in lru_cache_add
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On Thu, Nov 26, 2020 at 04:44:04PM +0100, Vlastimil Babka wrote:
> However, Matthew wanted to increase pagevec size [1] and once 15^2 becomes
> 63^2, it starts to be somewhat more worrying.
> 
> [1] https://lore.kernel.org/linux-mm/20201105172651.2455-1-willy@infradead.org/

Well, Tim wanted it ;-)

I would suggest that rather than an insertion sort (or was it a bubble
sort?), we should be using a Shell sort.  It's ideal for these kinds of
smallish arrays.

https://en.wikipedia.org/wiki/Shellsort