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Date: Mon, 1 Dec 2025 23:53:33 -0800
From: Christoph Hellwig <hch@infradead.org>
To: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Cc: clm@fb.comi, dsterba@suse.com, terrelln@fb.com,
	herbert@gondor.apana.org.au, linux-btrfs@vger.kernel.org,
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	brian.will@intel.com, weigang.li@intel.com,
	senozhatsky@chromium.org
Subject: Re: [RFC PATCH 00/16] btrfs: offload compression to hardware
 accelerators
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References: <20251128191531.1703018-1-giovanni.cabiddu@intel.com>
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On Fri, Nov 28, 2025 at 07:04:48PM +0000, Giovanni Cabiddu wrote:
> +---------------------------+---------+---------+---------+---------+
> |                           | QAT-L9  | ZSTD-L3 | ZLIB-L3 | LZO-L1  |
> +---------------------------+---------+---------+---------+---------+
> | Disk Write TPUT (GiB/s)   | 6.5     | 5.2     | 2.2     | 6.5     |
> +---------------------------+---------+---------+---------+---------+
> | CPU utils %age @208 cores | 4.56%   | 15.67%  | 12.79%  | 19.85%  |
> +---------------------------+---------+---------+---------+---------+
> | Compression Ratio         | 34%     | 35%     | 37%     | 58%     |
> +---------------------------+---------+---------+---------+---------+

Is it just me, or do the numbers not look all that great at least
when comparing to ZSTD-L3 and LZO-L1?  What are the decompression
numbers?