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Subject: Re: AW: Btrfs performance with small blocksize on SSD
To: "Fuhrmann, Carsten" <carsten.fuhrmann@rwth-aachen.de>,
        Qu Wenruo <quwenruo.btrfs@gmx.com>,
        "linux-btrfs@vger.kernel.org" <linux-btrfs@vger.kernel.org>
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From: Andrei Borzenkov <arvidjaar@gmail.com>
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Date: Sun, 24 Sep 2017 19:43:05 +0300
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24.09.2017 16:53, Fuhrmann, Carsten пишет:
> Hello,
> 
> 1)
> I used direct write (no page cache) but I didn't disable the Disk cache of the HDD/SSD itself. In all tests I wrote 1GB and looked for the runtime of that write process.

So "latency" on your diagram means total time to write 1GiB file? That
is highly unusual meaning for "latency" which normally means time to
perform single IO. If so, you should better rename Y-axis to something
like "total run time".