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Date: Thu, 28 Mar 2024 07:52:56 +0100
From: Christoph Hellwig <hch@lst.de>
To: Damien Le Moal <dlemoal@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>, linux-block@vger.kernel.org,
	Jens Axboe <axboe@kernel.dk>, linux-scsi@vger.kernel.org,
	"Martin K . Petersen" <martin.petersen@oracle.com>,
	dm-devel@lists.linux.dev, Mike Snitzer <snitzer@redhat.com>,
	linux-nvme@lists.infradead.org, Keith Busch <kbusch@kernel.org>
Subject: Re: [PATCH v3 09/30] block: Pre-allocate zone write plugs
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On Thu, Mar 28, 2024 at 03:51:09PM +0900, Damien Le Moal wrote:
> I am all for not micro-optimizing the free path right now.
> I am not so sure about the mempool being simpler... And I do see some
> improvements in perf for SMR HDDs with the free list. Could be noise though but
> it feels a little more solid perf-wise. I have not seen any benefit for faster
> devices with the free list though...
> 
> If you prefer the mempool, I can go back to using it though, not a big deal.

A capped free list + dynamic allocation beyond it is exactly what the
mempool is, so reimplementing seems a bit silly.