Не могу включить trim на ssd?

Question

[Kasheftin]

Не могу включить trim на ssd.
Ubuntu Server 12.04, Linux 3.11.0-15-generic.
Trim включил через discard в /etc/fstab. Впрочем, и через fstrim тоже не работает.

Проверяю так:

# for i in {1..100000}; do echo "1" >> tempfile; done
#sudo hdparm --fibmap tempfile
#sudo hdparm --read-sector 293865512 /dev/sda
#rm tempfile
#sync

После этого команда #sudo hdparm --read-sector 293865512 /dev/sda отдает все как в первый раз.

Результат команды #sudo fstrim -v /:
/: 0 bytes were trimmed

Вывод sudo hdparm -i /dev/sda

Model=KINGSTON SV300S37A240G, FwRev=520ABBF0, SerialNo=50026B7243004D3E
Config={ HardSect NotMFM HdSw>15uSec Fixed DTR>10Mbs RotSpdTol>.5% }
RawCHS=16383/16/63, TrkSize=0, SectSize=0, ECCbytes=4
BuffType=unknown, BuffSize=unknown, MaxMultSect=16, MultSect=1
CurCHS=16383/16/63, CurSects=16514064, LBA=yes, LBAsects=468862128
IORDY=on/off, tPIO={min:120,w/IORDY:120}, tDMA={min:120,rec:120}
PIO modes:  pio0 pio1 pio2 pio3 pio4 
DMA modes:  mdma0 mdma1 mdma2 
UDMA modes: udma0 udma1 udma2 udma3 udma4 udma5 *udma6 
AdvancedPM=yes: unknown setting WriteCache=disabled
Drive conforms to: unknown:  ATA/ATAPI-2,3,4,5,6,7

Вывод sudo hdparm -I /dev/sda

/dev/sda:

ATA device, with non-removable media
	Model Number:       KINGSTON SV300S37A240G                  
	Serial Number:      50026B7243004D3E    
	Firmware Revision:  520ABBF0
	Transport:          Serial, ATA8-AST, SATA 1.0a, SATA II Extensions, SATA Rev 2.5, SATA Rev 2.6, SATA Rev 3.0
Standards:
	Used: unknown (minor revision code 0x0110) 
	Supported: 8 7 6 5 
	Likely used: 8
Configuration:
	Logical		max	current
	cylinders	16383	16383
	heads		16	16
	sectors/track	63	63
	--
	CHS current addressable sectors:   16514064
	LBA    user addressable sectors:  268435455
	LBA48  user addressable sectors:  468862128
	Logical  Sector size:                   512 bytes
	Physical Sector size:                   512 bytes
	Logical Sector-0 offset:                  0 bytes
	device size with M = 1024*1024:      228936 MBytes
	device size with M = 1000*1000:      240057 MBytes (240 GB)
	cache/buffer size  = unknown
	Nominal Media Rotation Rate: Solid State Device
Capabilities:
	LBA, IORDY(can be disabled)
	Queue depth: 32
	Standby timer values: spec'd by Standard, with device specific minimum
	R/W multiple sector transfer: Max = 16	Current = 1
	Advanced power management level: 254
	DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 udma5 *udma6 
	     Cycle time: min=120ns recommended=120ns
	PIO: pio0 pio1 pio2 pio3 pio4 
	     Cycle time: no flow control=120ns  IORDY flow control=120ns
Commands/features:
	Enabled	Supported:
	   *	SMART feature set
	    	Security Mode feature set
	   *	Power Management feature set
	    	Write cache
	    	Look-ahead
	   *	Host Protected Area feature set
	   *	WRITE_BUFFER command
	   *	READ_BUFFER command
	   *	NOP cmd
	   *	DOWNLOAD_MICROCODE
	   *	Advanced Power Management feature set
	    	Power-Up In Standby feature set
	   *	SET_FEATURES required to spinup after power up
	    	SET_MAX security extension
	   *	48-bit Address feature set
	   *	Mandatory FLUSH_CACHE
	   *	FLUSH_CACHE_EXT
	   *	SMART error logging
	   *	SMART self-test
	   *	General Purpose Logging feature set
	   *	WRITE_{DMA|MULTIPLE}_FUA_EXT
	   *	64-bit World wide name
	   *	IDLE_IMMEDIATE with UNLOAD
	    	Write-Read-Verify feature set
	   *	{READ,WRITE}_DMA_EXT_GPL commands
	   *	Segmented DOWNLOAD_MICROCODE
	    	unknown 119[6]
	   *	Gen1 signaling speed (1.5Gb/s)
	   *	Gen2 signaling speed (3.0Gb/s)
	   *	Gen3 signaling speed (6.0Gb/s)
	   *	Native Command Queueing (NCQ)
	   *	Phy event counters
	   *	NCQ priority information
	   *	unknown 76[15]
	   *	DMA Setup Auto-Activate optimization
	    	Device-initiated interface power management
	   *	Software settings preservation
	   *	SMART Command Transport (SCT) feature set
	   *	SCT LBA Segment Access (AC2)
	   *	SCT Data Tables (AC5)
	   *	reserved 69[3]
	   *	DOWNLOAD MICROCODE DMA command
	   *	SET MAX SETPASSWORD/UNLOCK DMA commands
	   *	WRITE BUFFER DMA command
	   *	READ BUFFER DMA command
	   *	Data Set Management TRIM supported (limit 1 block)
Security: 
	Master password revision code = 65534
		supported
	not	enabled
	not	locked
	not	frozen
	not	expired: security count
		supported: enhanced erase
	4min for SECURITY ERASE UNIT. 2min for ENHANCED SECURITY ERASE UNIT.
Logical Unit WWN Device Identifier: 50026b7243004d3e
	NAA		: 5
	IEEE OUI	: 0026b7
	Unique ID	: 243004d3e
Checksum: correct

Вывод dmesg | grep discard

[    6.417350] EXT4-fs (sda1): re-mounted. Opts: discard,errors=remount-ro
[    6.471628] EXT4-fs (sdb1): mounted filesystem with ordered data mode. Opts: discard

Вывод cat /etc/mtab |grep discard

/dev/sda1 / ext4 rw,noatime,nodiratime,discard,errors=remount-ro 0 0
/dev/sdb1 /home/backup ext4 rw,noatime,nodiratime,discard 0 0

На двух других машинах с той же системой но другими ssd-дисками trim работает через discard в /etc/fstab.