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Date: Thu, 21 Dec 2023 20:42:13 +0000
From: Matthew Wilcox <willy@infradead.org>
To: Bart Van Assche <bvanassche@acm.org>
Cc: Hannes Reinecke <hare@suse.de>, lsf-pc@lists.linuxfoundation.org,
	linux-mm@kvack.org, linux-block@vger.kernel.org,
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	"linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>
Subject: Re: [LSF/MM/BPF TOPIC] Large block for I/O
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On Thu, Dec 21, 2023 at 12:33:08PM -0800, Bart Van Assche wrote:
> On 12/20/23 07:03, Hannes Reinecke wrote:
> > I would like to discuss
> > 
> > Large blocks for I/O
> > 
> > Since the presentation last year there has been quite some developments
> > and improvements in some areas, but at the same time a lack of progress
> > in other areas.
> > In this presentation/discussion I would like to highlight the current
> > state of affairs, existing pain points, and future directions of development.
> > It might be an idea to co-locate it with the MM folks as we do have
> > quite some overlap with page-cache improvements and hugepage handling.
> 
> Hi Hannes,
> 
> I'm interested in this topic. But I'm wondering whether the disadvantages of
> large blocks will be covered? Some NAND storage vendors are less than
> enthusiast about increasing the logical block size beyond 4 KiB because it
> increases the size of many writes to the device and hence increases write
> amplification.

It's LSF/MM.  If this session is being run as a presentation rather than
discussion, it's being done wrongly.  So if you want to talk about the
downsides, show up and talk about them.