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	Mon, 29 Jun 2026 12:40:22 +0000
Date: Mon, 29 Jun 2026 05:40:22 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Qu Wenruo <wqu@suse.com>
Cc: Rosen Penev <rosenp@gmail.com>, linux-btrfs@vger.kernel.org,
	Chris Mason <clm@fb.com>, David Sterba <dsterba@suse.com>,
	open list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] btrfs: raid56: use async_tx API for parity operations
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References: <20260629023912.2102700-1-rosenp@gmail.com>
 <d96ddcc0-a62f-40e4-9f80-34929dc3bcfd@suse.com>
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On Mon, Jun 29, 2026 at 02:41:44PM +0930, Qu Wenruo wrote:
> Do you have any benchmark?

Yeah.  The async_tx stuff is a mess, and will cause real slow downs
for CPU native operation, while in general offloads have proven to
not be very useful.  There might be a tinty use case if your data is
all P2P and never touches the CPU at all, but I don't think btrfs even
supports that right now.