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From: Martin <m_btrfs@ml1.co.uk>
To: linux-btrfs@vger.kernel.org
Subject: SSD erase state and reducing SSD wear
Date: Tue, 22 May 2012 22:47:42 +0100	[thread overview]
Message-ID: <jph1hu$2tq$1@dough.gmane.org> (raw)

I've got two recent examples of SSDs. Their pristine state from the
manufacturer shows:


Device Model:     OCZ-VERTEX3

# hexdump -C /dev/sdd
00000000  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|................|
*
1bf2976000


Device Model:     OCZ VERTEX PLUS
(OCZ VERTEX 2E)

# hexdump -C /dev/sdd
00000000 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
|................|
*
df99e6000



What's a good way to test what state they get erased to from a TRIM
operation?

Can btrfs detect the erase state and pad unused space in filesystem
writes with the same value so as to reduce SSD wear?

Regards,
Martin


             reply	other threads:[~2012-05-22 21:47 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-05-22 21:47 Martin [this message]
2012-05-23  4:19 ` SSD erase state and reducing SSD wear Calvin Walton
2012-05-23 15:44   ` Martin
2012-05-23 19:50     ` Calvin Walton

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