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To:     linux-ext4@vger.kernel.org
From:   ValdikSS <iam@valdikss.org.ru>
Subject: ext4lazyinit reads HDD data on mount since 5.13
Message-ID: <015c7506-7f33-3967-772a-1285b0f1052f@valdikss.org.ru>
Date:   Mon, 9 Aug 2021 01:13:03 +0300
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Hello,
After updating to kernel 5.13, my ext4 partition is read for ~20 seconds 
upon mounting by ext4lazyinit. It does not write anything, only reads 
(inspected with iotop), and it does so only on mount and only for 
relatively short amount of time.

My partition is several years old and have been fully initialized long 
ago. Mounting with `init_itable=0` did not change anything: ext4lazyinit 
does not write anything to begin with.

5.12.15 does not have such behavior. Did I miss a configuration change? 
Is that a regression or a new feature?