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Date:   Tue, 19 Oct 2021 20:58:49 +0800
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Subject: Re: [PATCH v2 3/3] erofs: introduce readmore decompression strategy
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To:     Gao Xiang <xiang@kernel.org>, linux-erofs@lists.ozlabs.org,
        LKML <linux-kernel@vger.kernel.org>, Yue Hu <zbestahu@gmail.com>,
        Gao Xiang <hsiangkao@linux.alibaba.com>
References: <20211008200839.24541-1-xiang@kernel.org>
 <20211008200839.24541-4-xiang@kernel.org>
 <8e39e5d1-285d-52b6-8fea-8bb9ff10bf5a@kernel.org>
 <20211017154253.GB4054@hsiangkao-HP-ZHAN-66-Pro-G1>
From:   Chao Yu <chao@kernel.org>
In-Reply-To: <20211017154253.GB4054@hsiangkao-HP-ZHAN-66-Pro-G1>
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On 2021/10/17 23:42, Gao Xiang wrote:
> On Sun, Oct 17, 2021 at 11:34:22PM +0800, Chao Yu wrote:
>> On 2021/10/9 4:08, Gao Xiang wrote:
>>> From: Gao Xiang <hsiangkao@linux.alibaba.com>
>>>
>>> Previously, the readahead window was strictly followed by EROFS
>>> decompression strategy in order to minimize extra memory footprint.
>>> However, it could become inefficient if just reading the partial
>>> requested data for much big LZ4 pclusters and the upcoming LZMA
>>> implementation.
>>>
>>> Let's try to request the leading data in a pcluster without
>>> triggering memory reclaiming instead for the LZ4 approach first
>>> to boost up 100% randread of large big pclusters, and it has no real
>>> impact on low memory scenarios.
>>>
>>> It also introduces a way to expand read lengths in order to decompress
>>> the whole pcluster, which is useful for LZMA since the algorithm
>>> itself is relatively slow and causes CPU bound, but LZ4 is not.
>>>
>>> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

Looks fine to me now.

Reviewed-by: Chao Yu <chao@kernel.org>

Thanks,