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Date:   Fri, 30 Apr 2021 12:59:48 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Shyam Prasad N <nspmangalore@gmail.com>
Cc:     Steve French <smfrench@gmail.com>,
        CIFS <linux-cifs@vger.kernel.org>,
        Jeff Layton <jlayton@redhat.com>,
        David Howells <dhowells@redhat.com>
Subject: Re: [PATCH] smb3: add rasize mount parameter to improve performance
 of readahead
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On Fri, Apr 30, 2021 at 04:19:27PM +0530, Shyam Prasad N wrote:
> Although ideally, I feel that we (cifs.ko) should be able to read in
> larger granular "chunks" even for small reads, in expectation that
> surrounding offsets will be read soon.

Why?  How is CIFS special and different from every other filesystem that
means you know what the access pattern of userspace is going to be better
than the generic VFS?

There are definitely shortcomings in the readahead code that should
be addressed, but in almost no circumstances is "read bigger chunks"
the right answer.