>>>>> "Chris" == Chris Samuel <chris@xxxxxxxxxxx> writes: Chris> It looks like drives that do support it can be detected with the Chris> kernel helper function ata_fpdma_dsm_supported() defined in Chris> include/linux/libata.h. Chris> I wonder if it would be possible to use that knowledge to extend Chris> the smartctl's --identify functionality to report this? Queued trim support is indicated in a log page and not the identify information. However, we can get to the information we want using smartctl's ability to look at log pages. I don't have a single drive from any vendor in the lab that supports queued trim, not even a prototype. I went out and bought a 840 EVO this morning because the general lazyweb opinion seemed to indicate that this drive supports queued trim. Well, it doesn't. At least not in the 120GB version: # smartctl -l gplog,0x13 /dev/sda smartctl 5.43 2012-06-30 r3573 [x86_64-linux-3.14.0-rc6+] (local build) Copyright (C) 2002-12 by Bruce Allen, http://smartmontools.sourceforge.net General Purpose Log 0x13 does not exist (override with '-T permissive' option) If there's a drive with a working queued trim implementation out there, I'd like to know about it... -- Martin K. Petersen Oracle Linux Engineering -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
