On Fri, Apr 15, 2016 at 11:49 AM, olli hauer <oha...@gmx.de> wrote: > On 2016-04-15 06:19, Warner Losh wrote: > > On Thu, Apr 14, 2016 at 9:56 PM, Warren Block <wbl...@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 .. >
I've done a lot of research for this issue. There's two reasons they were listed. One was a Linux kernel bug. The other was that early drives reported that it was supported when, in fact, it wasn't. I've constrained the list to the latter. Warner _______________________________________________ email@example.com mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"