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Subject: Re: BTRFS Mount Delay Time Graph
From:   Lionel Bouton <lionel-subscription@bouton.name>
To:     "Wilson, Ellis" <ellisw@panasas.com>,
        BTRFS <linux-btrfs@vger.kernel.org>
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 <4746e8ba-b20c-01e2-379e-b76f0d2ab5a7@bouton.name>
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Le 03/12/2018 à 20:56, Lionel Bouton a écrit :
> [...]
> Note : recently I tried upgrading from 4.9 to 4.14 kernels, various
> tuning of the io queue (switching between classic io-schedulers and
> blk-mq ones in the virtual machines) and BTRFS mount options
> (space_cache=v2,ssd_spread) but there wasn't any measurable improvement
> in mount time (I managed to reduce the mount of IO requests

Sent to quickly : I meant to write "managed to reduce by half the number
of IO write requests for the same amount of data writen"

>  by half on
> one server in production though although more tests are needed to
> isolate the cause).