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Date:   Thu, 27 Jul 2023 21:43:01 +0200
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Subject: Re: [PATCH] fuse: enable larger read buffers for readdir.
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To:     Miklos Szeredi <miklos@szeredi.hu>, Jaco Kroon <jaco@uls.co.za>
Cc:     Antonio SJ Musumeci <trapexit@spawn.link>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
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From:   Bernd Schubert <bernd.schubert@fastmail.fm>
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On 7/27/23 21:21, Miklos Szeredi wrote:
> On Wed, 26 Jul 2023 at 20:40, Jaco Kroon <jaco@uls.co.za> wrote:
> 
>> Will look into FUSE_INIT.  The FUSE_INIT as I understand from what I've
>> read has some expansion constraints or the structure is somehow
>> negotiated.  Older clients in other words that's not aware of the option
>> will follow some default.  For backwards compatibility that default
>> should probably be 1 page.  For performance reasons it makes sense that
>> this limit be larger.
> 
> Yes, might need this for backward compatibility.  But perhaps a
> feature flag is enough and the readdir buf can be limited to
> fc->max_read.

fc->max_read is set by default to ~0 and only set to something else when 
the max_read mount option is given? So typically that is a large value 
(UINT_MAX)?


Thanks,
Bernd