Attempting ATA TRIM on SAS devices?

[Garrett Wollman]

<<On Wed, 8 Jan 2014 20:36:13 -0000, "Steven Hartland" <killing at multiplay.co.uk> said:

> It should only do this if your drive reports it supports
> ATA_TRIM by setting the ATA_SUPPORT_DSM_TRIM bit in the
> response to an ATA_IDENTIFY command sent to it using ATA
> passthrough.

> What does the following report:
> camcontrol identify da12

It says:

pass13: <TALOS2 2.25> ATA-8 SATA 3.x device
pass13: 600.000MB/s transfers, Command Queueing Enabled

protocol              ATA/ATAPI-8 SATA 3.x
device model          TALOS2
firmware revision     2.25
serial number         A179E011337000251
WWN                   5e83a97a101b6024
cylinders             16383
heads                 16
sectors/track         63
sector size           logical 512, physical 512, offset 0
LBA supported         468883199 sectors
LBA48 supported       468883199 sectors
PIO supported         PIO4
DMA supported         WDMA2 UDMA6 
media RPM             non-rotating

Feature                      Support  Enabled   Value           Vendor
read ahead                     yes      no
write cache                    yes      no
flush cache                    yes      yes
overlap                        no
Tagged Command Queuing (TCQ)   no       no
Native Command Queuing (NCQ)   yes              32 tags
SMART                          yes      yes
microcode download             yes      yes
security                       yes      no
power management               yes      yes
advanced power management      yes      yes     254/0xFE
automatic acoustic management  no       no
media status notification      no       no
power-up in Standby            yes      no
write-read-verify              yes      no      0/0x0
unload                         yes      yes
free-fall                      no       no
Data Set Management (DSM/TRIM) yes
DSM - max 512byte blocks       yes              1
DSM - deterministic read       yes              any value
Host Protected Area (HPA)      yes      no      468883199/1
HPA - Security                 no

A very similar device (firmware 2.15 instead of 2.25) in a 9.1 system
returns no results to this command.  Not sure if that's 9.1/9.2
difference of a firmware difference.

-GAWollman