Re: Heads up

From: olli hauer <ohauer_at_gmx.de>
Date: Fri, 15 Apr 2016 19:49:33 +0200
On 2016-04-15 06:19, Warner Losh wrote:
> On Thu, Apr 14, 2016 at 9:56 PM, Warren Block <wblock_at_wonkity.com> wrote:
> 
>> On Thu, 14 Apr 2016, Warner Losh wrote:
>>
>> The CAM I/O scheduler has been committed to current. This work is described
>>> in https://people.freebsd.org/~imp/bsdcan2015/iosched-v3.pdf though the
>>> default scheduler doesn't change the default (old) behavior.
>>>
>>> One possible issue, however, is that it also enables NCQ Trims on ada
>>> SSDs.
>>> There are a few rogue drives that claim support for this feature, but
>>> actually implement data corrupt instead of queued trims. The list of known
>>> rogues is believed to be complete, but some caution is in order.
>>
>>
> 
>> Is the list of drives queryable?  Is there an easy way to tell if the
>> currently-connected drives are on the list?
>>
> 
> /usr/src/sys/cam/ata/ata_da.c has the list.
> 
> dmesg will tell you if it detected a bad one since it prints the drive's
> quirks.
> But that's no big deal, because the bad one work just fine if you never
> issue
> a NCQ TRIM. This small group of drives were early adapters of this
> technology
> 
> Here's the full list of known rogues:
> 
> Crucial/Micron M500 (all firmware prior to MU07)
> Micron M510 MU01 firmware (newer firmware is good)
> Crucial/Micron M550 MU01 firmware (newer firmware is good)
> Crucial MX100 MU01 firmware (newer firmware is good)
> FCCT M500 all firmware
> Samsung 830 all firmware
> Samsung 840 all firmware
> Samsung 850 all firmware
> 
> All of these are at least 18 months old (if not older). There's some
> confusing in Linux lists on
> the full impact of the Samsung drives (there was a bug in the Linux
> implementation (that can't
> be present in the FreeBSD implementation) that may have been the root cause
> for the Samsung
> black listing). Out of an abundance of caution, I've kept them in the list.
> Also, it's my belief that
> the Crucial/Micron models with MU01 firmware were mostly corrected after
> early samples
> since most of the channel drives I've helped people debug had MU02
> firmware. Also, a quick
> google search shows the MU02 firmware for each of these models has been
> available for
> at least a year.
> 
> Warner

I suspect this was the reason why Samsung SSD's are listed on the Linux blacklist.
https://blog.algolia.com/when-solid-state-drives-are-not-that-solid/

But the article also reports it was a Linux kernel issue ...
Received on Fri Apr 15 2016 - 15:44:59 UTC

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