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Date: Thu, 31 Oct 2024 14:02:51 +0100
From: Christoph Hellwig <hch@lst.de>
To: Hans Holmberg <hans@owltronix.com>
Cc: Keith Busch <kbusch@kernel.org>, Christoph Hellwig <hch@lst.de>,
	Keith Busch <kbusch@meta.com>, linux-block@vger.kernel.org,
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	Hannes Reinecke <hare@suse.de>
Subject: Re: [PATCHv10 9/9] scsi: set permanent stream count in block limits
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On Thu, Oct 31, 2024 at 09:19:51AM +0100, Hans Holmberg wrote:
> No. The meta data IO is just 0.1% of all writes, so that we use a
> separate device for that in the benchmark really does not matter.
> 
> Since we can achieve a WAF of ~1 for RocksDB on flash, why should we
> be content with another 67% of unwanted device side writes on top of
> that?
> 
> It's of course impossible to compare your benchmark figures and mine
> directly since we are using different devices, but hey, we definitely
> have an opportunity here to make significant gains for FDP if we just
> provide the right kernel interfaces.

I'll write code to do a 1:1 single device comparism over the weekend
and Hans will test it once he is back.