Solid state drive

This article covers special topics for operating solid state drives (SSDs) and other flash-memory based storage devices.

If you want to partition an SSD for a specific purpose, it may be useful to consider the List of file systems optimized for flash memory.

For general usage, simply choose your preferred filesystem and enable #TRIM.

Usage

TRIM

Most SSDs support the ATA_TRIM command for sustained long-term performance and wear-leveling. A TechSpot article shows performance benchmark examples of before and after filling an SSD with data.

As of Linux kernel version 3.8 onwards, support for TRIM was continually added for the different filesystems. See the following table for an indicative overview:

File system	Continuous TRIM (`discard` option)	Periodic TRIM (fstrim)	References and notes
Btrfs	Yes	Yes
exFAT	Yes	Yes	fstrim is supported since kernel 5.13,
ext3	Yes	Yes
ext4	Yes	Yes	"discard, nodiscard(*)" in
F2FS	Yes	Yes
JFS	Yes	Yes
NILFS2	Yes	Yes
NTFS-3G	No	Yes	since version 2015.3.14,
VFAT	Yes	Yes	fstrim is supported since kernel 4.19,
XFS	Yes	Yes

Warning: Users need to be certain that their SSD supports TRIM before attempting to use it. Data loss can occur otherwise!

To verify TRIM support, run:

$ lsblk --discard

And check the values of DISC-GRAN (discard granularity) and DISC-MAX (discard max bytes) columns. Non-zero values indicate TRIM support.

Alternatively, install hdparm package and run:

Periodic TRIM

The util-linux package provides and systemd unit files. Enabling the timer will activate the service weekly. The service executes on all mounted filesystems on devices that support the discard operation.

The timer relies on the timestamp of (which it will create upon first invocation) to know whether a week has elapsed since it last ran. Therefore there is no need to worry about too frequent invocations, in an anacron-like fashion.

To query the units activity and status, see journalctl. To change the periodicity of the timer or the command run, edit the provided unit files.

Continuous TRIM

Instead of issuing TRIM commands once in a while (by default once a week if using ), it is also possible to issue TRIM commands each time files are deleted instead. The latter is known as the continuous TRIM.

Note: Continuous TRIM is not the most preferred way to issue TRIM commands among the Linux community. For example, Ubuntu enables periodic TRIM by default , Debian does not recommend using continuous TRIM and Red Hat recommends using periodic TRIM over using continuous TRIM if feasible .

Using the discard option for a mount in enables continuous TRIM in device operations:

/dev/sda1  /           ext4  defaults,discard   0  1

On the ext4 filesystem, the discard flag can also be set as a default mount option using tune2fs:

# tune2fs -o discard /dev/sdXY

Using the default mount options instead of an entry in is particularly useful for external drives, because such partition will be mounted with the default options also on other machines. This way, there is no need to edit on every machine.

Trim an entire device

If you want to trim your entire SSD at once, e.g. for a new install or if you want to sell the drive, you can use the blkdiscard command.

LVM

TRIM requests that get passed from the file system to the logical volume are automatically passed to the physical volume(s). No additional configuration is necessary.

No LVM operations (lvremove, lvreduce and all others) issue TRIM requests to physical volume(s) by default. This is done to allow restoring previous volume group configuration with vgcfgrestore(8). The setting in controls whether discards are sent to a logical volume's underlying physical volumes when the logical volume is no longer using the physical volumes' space.

dm-crypt

For non-root filesystems, configure /etc/crypttab to include discard in the list of options for encrypted block devices located on an SSD (see dm-crypt/System configuration#crypttab).

For the root filesystem, follow the instructions from dm-crypt/Specialties#Discard/TRIM support for solid state drives (SSD) to add the right kernel parameter to the bootloader configuration.

Maximizing performance

Follow the tips in Improving performance#Storage devices to maximize the performance of your drives.

Sector size

See Advanced Format#Solid state drives.

SSD memory cell clearing

On occasion, users may wish to completely reset an SSD's cells to the same virgin state they were at the time the device was installed, thus restoring it to its factory default write performance. Write performance is known to degrade over time even on SSDs with native TRIM support: TRIM only safeguards against file deletes, not replacements such as an incremental save.

The reset can be accomplished by following the appropriate procedure denoted in SSD memory cell clearing, either for #SATA or #NVMe SSDs.

Hdparm shows "frozen" state

Some motherboard BIOS' issue a "security freeze" command to SATA devices on initialization. Likewise some SSD (and HDD) BIOS' are set to "security freeze" in the factory already. Both result in the device's password security settings to be set to frozen, as shown in below output:

Operations like formatting the device or installing operating systems are not affected by the "security freeze".

The above output shows the device is not locked by a HDD-password on boot and the frozen state safeguards the device against malwares which may try to lock it by setting a password to it at runtime.

If you intend to set a password to a "frozen" device yourself, a motherboard BIOS with support for it is required. A lot of notebooks have support, because it is required for hardware encryption, but support may not be trivial for a desktop/server board. For the Intel DH67CL/BL motherboard, for example, the motherboard has to be set to "maintenance mode" by a physical jumper to access the settings (see , ).

If you intend to erase the SSD, see Securely wipe disk#hdparm and /Memory cell clearing.

Setting the SSD state to "frozen" after waking up from sleep

When waking up from sleep, the SSD will most likely have lost its "frozen" status, leaving it vulnerable to ATA SECURE ERASE commands like those described in /Memory cell clearing.

In order to prevent this issue, a script can be run after waking up from sleep:

Hardware encryption

As noted in #Hdparm shows "frozen" state setting a password for a storage device (SSD/HDD) in the BIOS may also initialize the hardware encryption of devices supporting it. If the device also conforms to the OPAL standard, this may also be achieved without a respective BIOS feature to set the passphrase, see Self-encrypting drives.

Troubleshooting

It is possible that the issue you are encountering is a firmware bug which is not Linux specific, so before trying to troubleshoot an issue affecting the SSD device, you should first check if updates are available for:

The SSD's firmware
The motherboard's BIOS/UEFI firmware

Even if it is a firmware bug it might be possible to avoid it, so if there are no updates to the firmware or you hesitant on updating firmware then the following might help.

Resolving NCQ errors

Some SSDs and SATA chipsets do not work properly with Linux Native Command Queueing (NCQ). The tell-tale dmesg errors look like this:

[ 9.115544] ata9: exception Emask 0x0 SAct 0xf SErr 0x0 action 0x10 frozen
[ 9.115550] ata9.00: failed command: READ FPDMA QUEUED
[ 9.115556] ata9.00: cmd 60/04:00:d4:82:85/00:00:1f:00:00/40 tag 0 ncq 2048 in
[ 9.115557] res 40/00:18:d3:82:85/00:00:1f:00:00/40 Emask 0x4 (timeout)

To disable NCQ on boot, add libata.force=noncq to the kernel command line in the bootloader configuration. To disable NCQ only for disk 0 on port 9 use:

Alternatively, you may disable NCQ for a specific drive without rebooting via sysfs:

# echo 1 > /sys/block/sdX/device/queue_depth

If this (and also updating the firmware) does not resolve the problem or causes other issues, then file a bug report.

Resolving SATA power management related errors

Some SSDs (e.g. Transcend MTS400) are failing when SATA Active Link Power Management, ALPM, is enabled. ALPM is disabled by default and enabled by a power saving daemon (e.g. TLP, Laptop Mode Tools).

If you are starting to encounter SATA related errors when using such a daemon, you should try to disable ALPM by setting its state to for both battery and AC powered profiles.

External SSD with TRIM support

Several USB-to-SATA bridge chips (like VL715, VL716 etc.) and also USB-to-PCIe bridge chips (like the JMicron JMS583 used in external NVMe enclosures like IB-1817M-C31) support TRIM-like commands that can be sent through the USB Attached SCSI driver (named "uas" under Linux).

But the kernel may not automatically detect this capability, and therefore might not use it. Assuming your block device in question is /dev/sdX, you can find out whether that is the case by using the command

# sg_readcap -l /dev/sdX

If in its output you find a line stating "Logical block provisioning: lbpme=0" then you know that the kernel assumes the device does not support "Logical Block Provisioning Management" because the (LBPME) bit is not set.

If this is the case, then you should next find out whether the "Vital Product Data" (VPD) page on "Logical Block Provisioning" of your device tells of supported mechanisms for unmapping data. You can do this using the command:

# sg_vpd -a /dev/sdX

Look for lines in the output that look like this:

Unmap command supported (LBPU): 1
Write same (16) with unmap bit supported (LBPWS): 0
Write same (10) with unmap bit supported (LBPWS10): 0

This example would tell you the device supports the "UNMAP" command.

Have a look at the output of

$ cat /sys/block/sdX/device/scsi_disk/*/provisioning_mode

If the kernel did not detect the capability of your device to unmap data, then this will likely return "full". Apart from "full", the kernel SCSI storage driver currently knows the following values for provisioning_mode:

unmap
writesame_16
writesame_10
writesame_zero
disabled

For the example above, you could now write "unmap" to "provisioning_mode" to ask the kernel to use that:

# echo "unmap" >/sys/block/sdX/device/scsi_disk/*/provisioning_mode

This should immediately enable you to use tools like "blkdiscard" on /dev/sdX or "fstrim" on filesystems mounted on /dev/sdX.

If you want to enable a "provisioning_mode" automatically when an external device of a certain vendor/product is attached, this can be automated via the "udev" mechanism. First find the USB Vendor and Product IDs:

$ cat /sys/block/sdX/../../../../../../idVendor
$ cat /sys/block/sdX/../../../../../../idProduct

Then create or append to a udev rule file (example here using idVendor 152d and idProduct 0583):

# echo 'ACTION=="add|change", ATTRS{idVendor}=="152d", ATTRS{idProduct}=="0583", SUBSYSTEM=="scsi_disk", ATTR{provisioning_mode}="unmap"' >>/etc/udev/rules.d/10-uas-discard.rules

(You can also use the command to look for the relevant idVendor/idProduct.)

Firmware

If supported by the device vendor, it is recommended to update firmware using the fwupd utility.

ADATA

Updating SSD firmware under Linux is not supported by ADATA. A Windows-only utility called SSD ToolBox is provided by ADATA through their support page and through their ADATA XPG support page to monitor, TRIM, benchmark and update ADATA SSD firmware.

Crucial

Crucial provides an option for updating the firmware with an ISO image. These images can be found after selecting the product on their SSD support page and downloading the "Manual Boot File."

Note: ISO images provided by Crucial do not seem to be hybrid. If you will use just the dd command to copy the image to some device, the MBR will not be present, making such device unbootable.

Owners of an M4 Crucial model, may check if a firmware upgrade is needed with .

Users seeing this warning are advised to backup all sensible data and consider upgrading immediately. Check this instructions to update Crucial MX100 firmware by using the ISO image and Grub.

Intel

Intel has a Linux live system based Firmware Update Tool for operating systems that are not compatible with its Windows Intel® Memory and Storage Tool (GUI) software.

There is also a newer Linux command-line utility that can reflash firmware called the Intel Memory and Storage (MAS) Tool available as . There is a PDF user guide available.

An example for checking the firmware status is:

can be omitted if there is only one Intel SSD in the system, or 1 passed for the second SSD, and so on.

If an update is available, it is performed by running . The PDF user guide suggests that this procedure needs to be performed twice in Linux, with a power cycle in between. The latest firmware for all devices is distributed as part of the MAS Tool itself, so does not need to be downloaded separately.

Kingston

KFU tool is available for the Sandforce based drives, .

Mushkin

The lesser known Mushkin brand solid state drives also use Sandforce controllers, and have a Linux utility (nearly identical to Kingston's) to update the firmware.

OCZ

OCZ has a Command Line Online Update Tool (CLOUT) available for Linux. The existing packages are , ocztoolbox^AUR and .

Samsung

Although Samsung deems firmware update methods outside of their Magician software as "unsupported", they still can work. The Magician software can create a bootable USB drive containing the firmware update, however Samsung no longer provides the software for consumer SSDs. Samsung also provides pre-made bootable ISO images that can be used to update the firmware. Another option is to use Samsung's magician utility provided by . Magician only supports Samsung-branded SSDs; those manufactured by Samsung for OEMs (e.g., Lenovo) are not supported.

Users preferring to run the firmware update from a live USB created under Linux (without using Samsung's Magician software under Microsoft Windows) can refer to for more details.

Update under Linux

The SSD firmware can be updated natively (without making a bootable USB stick) as shown below. First visit the Samsung downloads page, go to the "Samsung SSD Firmware" section, and download the latest firmware for your SSD—it should be an ISO image.

Extract the Linux image from the ISO image:

$ bsdtar xf samsung_ssd_firmware.iso initrd

Extract . This directory contains the firmware update files:

$ bsdtar xf initrd root/fumagician

Finally, run with root privileges and reboot your system (if the firmware was successfully updated).

Older SSDs

Some of the SSD firmware ISO images contain a FreeDOS image instead of an Linux image, so the steps needed to update the SSD firmware differ from above. The following table lists these SSDs (and relevant paths):

SSD model	FreeDOS image path	Firmware package path
470, 830		`SSR/`
840	`isolinux/btdsk.img`
840 EVO (mSATA), Pro

First, extract the FreeDOS image from the ISO image:

$ bsdtar xf samsung_ssd_firmware.iso freedos_image_path

Mount the FreeDOS image to :

# mount freedos_image_path /mnt

Get the disk number of the SSD under Disk Number from the Magician SSD management utility:

# magician --list

Update the SSD firmware for the specified disk by providing the firmware package path:

# magician --disk disk_num --firmware-update --fwpackage-path /mnt/firmware_package_path

Finally, verify whether the firmware was successfully updated by checking the version under Firmware from the output of (with root privileges). Reboot your system if so.

SanDisk

SanDisk makes ISO firmware images to allow SSD firmware update on operating systems that are unsupported by their SanDisk SSD Toolkit.

One must choose the firmware for the correct SSD model, and the correct capacity that it has (e.g. 60GB, or 256GB). After burning the ISO firmware image, simply restart the PC to boot with the newly created CD/DVD boot disk (may work from a USB stick).

The iso images just contain a linux kernel and an initrd. Extract them to partition and boot them with GRUB or Syslinux to update the firmware.