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Date:   Tue, 14 Sep 2021 12:45:24 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Hamza Mahfooz <someguy@effective-light.com>
Cc:     linux-kernel@vger.kernel.org, Benjamin LaHaise <bcrl@kvack.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>, linux-aio@kvack.org,
        linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] aio: convert active_reqs into a hashtable
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On Tue, Sep 14, 2021 at 05:46:25AM -0400, Hamza Mahfooz wrote:
> Commit 833f4154ed56 ("aio: fold lookup_kiocb() into its sole caller")
> suggests that, the fact that active_reqs is a linked-list means aio_kiocb
> lookups in io_cancel() are inefficient. So, to get faster lookups (on
> average) while maintaining similar insertion and deletion characteristics,
> turn active_reqs into a hashtable.

What workload cares about AIO cancellation performance?