From: Ferry Toth <ftoth@exalondelft.nl>
To: linux-btrfs@vger.kernel.org
Subject: Hot data tracking / hybrid storage
Date: Sun, 15 May 2016 12:12:09 +0000 (UTC) [thread overview]
Message-ID: <nh9p2p$cns$1@ger.gmane.org> (raw)
Is there anything going on in this area?
We have btrfs in RAID10 using 4 HDD's for many years now with a rotating
scheme of snapshots for easy backup. <10% files (bytes) change between
oldest snapshot and the current state.
However, the filesystem seems to become very slow, probably due to the
RAID10 and the snapshots.
It would be fantastic if we could just add 4 SSD's to the pool and btrfs
would just magically prefer to put often accessed files there and move
older or less popular files to the HDD's.
In my simple mind this can not be done easily using bcache as that would
require completely rebuilding the file system on top of bcache (can not
just add a few SSD's to the pool), while implementing a cache inside btrfs
is probably a complex thing with lots of overhead.
Simply telling the allocator to prefer new files to go to the ssd and
move away unpopular stuff to hdd during balance should do the trick, or am
I wrong?
Are none of the big users looking into this?
Ferry
next reply other threads:[~2016-05-15 12:12 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-05-15 12:12 Ferry Toth [this message]
2016-05-15 21:11 ` Hot data tracking / hybrid storage Duncan
2016-05-15 23:05 ` Kai Krakow
2016-05-17 6:27 ` Ferry Toth
2016-05-17 11:32 ` Austin S. Hemmelgarn
2016-05-17 18:33 ` Kai Krakow
2016-05-18 22:44 ` Ferry Toth
2016-05-19 18:09 ` Kai Krakow
2016-05-19 18:51 ` Austin S. Hemmelgarn
2016-05-19 21:01 ` Kai Krakow
2016-05-20 11:46 ` Austin S. Hemmelgarn
2016-05-19 23:23 ` Henk Slager
2016-05-20 12:03 ` Austin S. Hemmelgarn
2016-05-20 17:02 ` Ferry Toth
2016-05-20 17:59 ` Austin S. Hemmelgarn
2016-05-20 21:31 ` Henk Slager
2016-05-29 6:23 ` Andrei Borzenkov
2016-05-29 17:53 ` Chris Murphy
2016-05-29 18:03 ` Holger Hoffstätte
2016-05-29 18:33 ` Chris Murphy
2016-05-29 20:45 ` Ferry Toth
2016-05-31 12:21 ` Austin S. Hemmelgarn
2016-06-01 10:45 ` Dmitry Katsubo
2016-05-20 22:26 ` Henk Slager
2016-05-23 11:32 ` Austin S. Hemmelgarn
2016-05-16 11:25 ` Austin S. Hemmelgarn
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