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Date:   Mon, 22 Mar 2021 14:57:18 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Sergey Senozhatsky <senozhatsky@chromium.org>
Cc:     Matthew Wilcox <willy@infradead.org>,
        Namjae Jeon <namjae.jeon@samsung.com>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-cifs@vger.kernel.org,
        linux-cifsd-devel@lists.sourceforge.net, smfrench@gmail.com,
        hyc.lee@gmail.com, viro@zeniv.linux.org.uk, hch@lst.de,
        hch@infradead.org, ronniesahlberg@gmail.com,
        aurelien.aptel@gmail.com, aaptel@suse.com, sandeen@sandeen.net,
        dan.carpenter@oracle.com, colin.king@canonical.com,
        rdunlap@infradead.org,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Steve French <stfrench@microsoft.com>
Subject: Re: [PATCH 3/5] cifsd: add file operations
Message-ID: <20210322135718.GA28451@lst.de>
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On Mon, Mar 22, 2021 at 06:03:21PM +0900, Sergey Senozhatsky wrote:
> On (21/03/22 08:15), Matthew Wilcox wrote:
> > 
> > What's the scenario for which your allocator performs better than slub
> > 
> 
> IIRC request and reply buffers can be up to 4M in size. So this stuff
> just allocates a number of fat buffers and keeps them around so that
> it doesn't have to vmalloc(4M) for every request and every response.

Do we have any data suggesting it is faster than vmalloc?