From: Chris Samuel <chris@csamuel.org>
To: linux-btrfs@vger.kernel.org
Subject: Re: discard synchronous on most SSDs?
Date: Sat, 15 Mar 2014 16:25:05 +1100 [thread overview]
Message-ID: <4448214.x9oPWjPhdL@quad> (raw)
In-Reply-To: <yq1bnx8y2mi.fsf@sermon.lab.mkp.net>
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On Fri, 14 Mar 2014 03:57:41 PM Martin K. Petersen wrote:
> The fact that the drive reports compliance with a certain version of
> SATA does not in any way imply that it implements all commands defined
> in that specification.
It looks like drives that do support it can be detected with the kernel helper
function ata_fpdma_dsm_supported() defined in include/linux/libata.h.
I wonder if it would be possible to use that knowledge to extend the
smartctl's --identify functionality to report this?
Not even all drives that implement it do so correctly, the kernel has a
blacklist of drives that don't and currently lists just two:
/* devices that don't properly handle queued TRIM commands */
{ "Micron_M500*",· · NULL,· ATA_HORKAGE_NO_NCQ_TRIM, },
{ "Crucial_CT???M500SSD*",· NULL,· ATA_HORKAGE_NO_NCQ_TRIM, },
cheers,
Chris
--
Chris Samuel : http://www.csamuel.org/ : Melbourne, VIC
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next prev parent reply other threads:[~2014-03-15 5:25 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-09 7:48 Massive BTRFS performance degradation KC
2014-03-09 8:17 ` Swâmi Petaramesh
2014-03-09 10:01 ` Martin Steigerwald
2014-03-09 10:23 ` Swâmi Petaramesh
2014-03-09 11:33 ` Hugo Mills
2014-03-09 11:54 ` Martin Steigerwald
2014-03-09 12:10 ` Swâmi Petaramesh
2014-03-09 17:14 ` boris
2014-03-14 2:11 ` discard synchronous on most SSDs? Marc MERLIN
2014-03-14 3:39 ` Chris Murphy
2014-03-14 5:17 ` Marc MERLIN
2014-03-14 7:33 ` Chris Samuel
2014-03-14 19:26 ` Marc MERLIN
2014-03-14 19:57 ` Martin K. Petersen
2014-03-14 20:46 ` Holger Hoffstätte
2014-03-15 4:21 ` Marc MERLIN
2014-03-15 9:38 ` Holger Hoffstätte
2014-03-15 5:25 ` Chris Samuel [this message]
2014-03-15 6:48 ` Chris Samuel
2014-03-15 11:26 ` Duncan
2014-03-15 22:48 ` Chris Samuel
2014-03-16 6:06 ` Marc MERLIN
2014-03-16 17:09 ` Chris Murphy
2014-03-16 16:22 ` Martin K. Petersen
2014-03-16 17:50 ` Marc MERLIN
2014-03-15 4:06 ` Chris Samuel
2014-03-16 16:07 ` Martin K. Petersen
2014-03-14 12:07 ` Duncan
2014-03-14 21:44 ` Chris Murphy
2014-03-14 7:27 ` Chris Samuel
2014-03-09 17:36 ` Massive BTRFS performance degradation Austin S Hemmelgarn
2014-03-09 18:55 ` Tobias Holst
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