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Date: Mon, 17 Sep 2012 19:15:30 +0800
From: ching <lsching17@gmail.com>
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To: "linux-btrfs@vger.kernel.org" <linux-btrfs@vger.kernel.org>
Subject: enquiry about autodefrag option (resent)
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I am testing btrfs for long-term storage and backup, and i would like
to know more about "autodefrag" option:

1. Will "autodefrag" option benefit ssd?

    My understanding is:

       autodrag -> number of extent decrease -> metadata decrease -> a
"healthier" filesystem in the long run

   (P.S. I am aware that autodefrag will introduce extra write I/O)

2. AFAIK, "autodefrag" detects small random writes into files and
queues them up for an automatic defrag process, so the filesystem will
defragment itself while it's used.

    If the system reboot/crash/remount-ro, will the autodefrag process
continue after resume?