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Date: Wed, 26 Oct 2016 00:36:19 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Andreas Dilger <adilger@dilger.ca>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>,
        Christoph Hellwig <hch@infradead.org>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
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Subject: Re: [PATCHv4 18/43] block: define BIO_MAX_PAGES to HPAGE_PMD_NR if
 huge page cache enabled
Message-ID: <20161026073619.GB1128@infradead.org>
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On Tue, Oct 25, 2016 at 10:13:13PM -0600, Andreas Dilger wrote:
> Why wouldn't you have all the pool sizes in between?  Definitely 1MB has
> been too small already for high-bandwidth IO.  I wouldn't mind BIOs up to
> 4MB or larger since most high-end RAID hardware does best with 4MB IOs.

I/O sizes are not limited by the bio size, we can already support larger
than 1MB I/O for a long time.