From: Andrei Borzenkov <arvidjaar@gmail.com>
To: Hans van Kranenburg <hans.van.kranenburg@mendix.com>,
"Ellis H. Wilson III" <ellisw@panasas.com>,
linux-btrfs@vger.kernel.org
Subject: Re: btrfs-cleaner / snapshot performance analysis
Date: Sun, 11 Feb 2018 12:31:42 +0300 [thread overview]
Message-ID: <437ef3be-58ef-9195-0422-113b5fd17bff@gmail.com> (raw)
In-Reply-To: <13d35a99-98ef-5861-3b44-17428d999a7c@mendix.com>
11.02.2018 04:02, Hans van Kranenburg пишет:
...
>
>> - /dev/sda6 / btrfs
>> rw,relatime,ssd,space_cache,subvolid=259,subvol=/@/.snapshots/1/snapshot
>> 0 0
>
> Note that changes on atime cause writes to metadata, which means cowing
> metadata blocks and unsharing them from a previous snapshot, only when
> using the filesystem, not even when changing things (!).
With relatime atime is updated only once after file was changed. So your
description is not entirely accurate and things should not be that
dramatic unless files are continuously being changed.
next prev parent reply other threads:[~2018-02-11 9:31 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-02-09 16:45 btrfs-cleaner / snapshot performance analysis Ellis H. Wilson III
2018-02-09 17:10 ` Peter Grandi
2018-02-09 20:36 ` Hans van Kranenburg
2018-02-10 18:29 ` Ellis H. Wilson III
2018-02-10 22:05 ` Tomasz Pala
2018-02-11 15:59 ` Ellis H. Wilson III
2018-02-11 18:24 ` Hans van Kranenburg
2018-02-12 15:37 ` Ellis H. Wilson III
2018-02-12 16:02 ` Austin S. Hemmelgarn
2018-02-12 16:39 ` Ellis H. Wilson III
2018-02-12 18:07 ` Austin S. Hemmelgarn
2018-02-13 13:34 ` E V
2018-02-11 1:02 ` Hans van Kranenburg
2018-02-11 9:31 ` Andrei Borzenkov [this message]
2018-02-11 17:25 ` Adam Borowski
2018-02-11 16:15 ` Ellis H. Wilson III
2018-02-11 18:03 ` Hans van Kranenburg
2018-02-12 14:45 ` Ellis H. Wilson III
2018-02-12 17:09 ` Hans van Kranenburg
2018-02-12 17:38 ` Ellis H. Wilson III
2018-02-11 6:40 ` Qu Wenruo
2018-02-14 1:14 ` Darrick J. Wong
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