Solid state drive

Related articles
Solid state drive/NVMe
Solid state drive/Memory cell clearing
Benchmarking/Data storage devices
Improving performance#Storage devices
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
file system
and enable
#TRIM
.
Usage
TRIM
Compared to hard drives, where deleting a file is only handled at the file system level
[1]
, SSDs benefit from informing the disk controller when blocks of memory are free to be reused. Since the flash cells they are made of are worn out a little with each write operation, the disk controllers use algorithms to share the write operations on all the cells: this process is called
wear leveling
. Without the NVMe
DEALLOCATE
, SAS
UNMAP
or
ATA_TRIM
command (supported by most SSDs), the disk controller takes more time to do a write operation as soon as there is no empty memory blocks, as it has to shuffle data around to erase a cell before writing to it (see
Wikipedia:Write amplification
): a
TechSpot benchmark
shows the performance impact before and after filling an SSD with data.
Note
If you want to use TRIM, use
either
periodic TRIM or continuous TRIM. Continuous TRIM is
not
the most preferred way to issue TRIM commands among the Linux community. For example, Ubuntu enables periodic TRIM by default
[2]
, Debian does not recommend using
continuous TRIM
and Red Hat recommends using periodic TRIM over using continuous TRIM if feasible
[3]
.
As of Linux kernel version 3.8 onwards, support for TRIM was continually added for the different
file systems
. See the following table for an indicative overview:
File system
Continuous TRIM
(
discard
option)
Periodic TRIM
(
fstrim
)
References
and notes
Bcachefs
Yes
No
Btrfs
Yes
Yes
Asynchronous discard is
enabled
by default since kernel 6.2.
exFAT
Yes
Yes
fstrim
is supported since kernel 5.13,
[4]
ext3
Yes
Yes
ext4
Yes
Yes
"discard, nodiscard(*)" in
[5]
F2FS
Yes
Yes
JFS
Yes
Yes
[6]
NILFS2
Yes
Yes
NTFS
Yes
No
ntfs3
kernel driver only supports continuous TRIM.
No
Yes
NTFS-3G
driver only supports periodic TRIM.
VFAT
Yes
Yes
fstrim
is supported since kernel 4.19,
[7]
XFS
Yes
Yes
[8]
Swap
Yes
No
Not technically a "file system", but TRIM is still relevant. The "once" option provides scheduled trimming at startup. See
swapon(8)
.
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.
For SATA SSDs only, the
hdparm
package can detect TRIM support via
hdparm -I /dev/sda | grep TRIM
as the
root user
.
hdparm
does however not support NVMe SSDs.
Periodic TRIM
The
util-linux
package provides
fstrim.service
and
fstrim.timer
systemd
unit files.
Enabling
the timer will activate the service weekly. The service executes
fstrim(8)
on all mounted file systems on devices that support the
discard
operation.
The timer relies on the timestamp of
/var/lib/systemd/timers/stamp-fstrim.timer
(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
fstrim.timer
), it is also possible to issue TRIM commands each time files are deleted instead. The latter is known as the continuous TRIM.
Warning
Before
SATA 3.1
all TRIM commands were non-queued, so continuous trimming would produce frequent system freezes. In this case, applying
#Periodic TRIM
less often is better alternative. Similar issue holds also for a number of devices, see the
__ata_dev_quirks
entries with
ATA_QUIRK_NO_NCQ_TRIM
in
Linux source code
, for which queued TRIM command execution was blacklisted due to serious data corruption. In such case, depending on the device, the system may be forced to send non-queued TRIM commands the SSD instead of queued TRIM. See
Wikipedia:Trim_(computing)#Disadvantages
for details.
Using the
discard
option for a mount in
/etc/fstab
enables continuous TRIM in device operations. For example:
/dev/disk/by-designator/root  /  ext4  defaults,
discard
0 1
Note
Specifying the discard mount option in
/etc/fstab
does not work with an XFS
/
partition. According to
this thread
, it has to be set using the
rootflags=discard
kernel parameter
.
On the ext4 file system, the
discard
flag can also be set as a
default mount option
using
tune2fs
:
# tune2fs -o discard /dev/sd
XY
Using the default mount options instead of an entry in
/etc/fstab
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
/etc/fstab
on every machine.
Note
The default mount options are not listed in
/proc/mounts
.
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.
Trim unpartitioned space
fdisk
can trim only the free space sectors between partitions so that those sectors may be reused for wear levelling. Use the
T
command, and press
f
at the prompt that follows.
Or use the
--discard-free
option in
sfdisk
:
# sfdisk --discard-free /dev/sd
X
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
issue_discards
in
/etc/lvm/lvm.conf
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.
Note
Carefully read the comment in
/etc/lvm/lvm.conf
before changing the
issue_discards
setting. It does not in any way affect TRIM requests that get passed from the file system to the disk (e.g. file deletions inside a file system) nor does it affect space management within a thin pool.
Warning
Enabling
issue_discards
will prevent volume group metadata restoration with
vgcfgrestore
. There will be no recovery options in case of a mistakenly issued LVM command.
dm-crypt
Warning
dm-crypt supports passing through discard requests to the underlying block device. This may or may not improve performance on SSD storage
[9]
, but has security implications, so it is not enabled by default.
Follow the instructions in
dm-crypt/Specialties#Discard/TRIM support for solid state drives (SSD)
to enable discard support for LUKS and plain dm-crypt devices.
swap
To enable discard for swap space, either add the
discard
option to a swap device's entry in
fstab
or pass
--discard
when calling
swapon
.
Discard is
not
automatically enabled for swap partitions when using
GPT partition automounting
.
See
swapon(8)
for discussion on when swap is discarded:
discard=once
or
discard=pages
. If
discard
is specified without a specific mode, the default is to enable both.
Warning
Enabling discard on RAID setups using mdadm will cause system lockup on boot and during runtime, if using swapon.
Maximizing performance
Follow the tips in
Improving performance#Storage devices
to maximize the performance of your 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
Solid state drive/Memory cell clearing
, either for
SATA
or
NVMe
SSDs.
Note
If the reason for the reset is to wipe data, you may not want to rely on the SSD controller to perform it securely,
e.g.
if you do not trust the manufacturer or are wary of potential bugs. In this case, see
Securely wipe disk#Flash memory
for further information and examples to perform a manual wipe.
Security
Frozen mode
Some motherboard firmware issue a ATA SECURITY FREEZE LOCK command to SATA devices on initialization, setting the drive to frozen mode which transitions it to SEC2 state (security disabled, not locked, frozen). Likewise some SSD (and HDD) are set to this state in the factory already. This can be seen in
hdparm
and
smartctl
output:
# hdparm -I /dev/sda
Security:
 	Master password revision code = 65534
 		supported
not	enabled
not	locked
frozen
not	expired: security count
 		supported: enhanced erase
 	4min for SECURITY ERASE UNIT. 2min for ENHANCED SECURITY ERASE UNIT.
# smartctl -g security /dev/sda
ATA Security is:  Disabled, frozen [SEC2]
Operations like formatting the device or installing operating systems are not affected by the frozen mode.
The above
hdparm
output shows the device is
not locked
by an 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.
[10]
Warning
Do not try to change the above
lock
security settings with
hdparm
unless you know exactly what you are doing.
If you intend to erase the SSD, see
Securely wipe disk#hdparm
and
/Memory cell clearing
.
Setting the SATA SSD state to frozen mode after waking up from sleep
When waking up from S3 sleep, the SATA SSD will most likely have reverted to SEC1 state (security disabled, not locked, not frozen), leaving it vulnerable to ATA SECURITY ERASE UNIT commands like those described in
/Memory cell clearing
.
In order to prevent this issue, a script can be run
after waking up from sleep
:
/usr/lib/systemd/system-sleep/ssd-freeze.sh
#!/bin/sh
if [ "$1" = 'post' ]; then
	sleep 1
	if hdparm --security-freeze /dev/disk/by-id/
ata-name-of-disk
; then
		logger "$0: SSD freeze command executed successfully"
	else
		logger "$0: SSD freeze command failed"
	fi	
fi
If the system has multiple storage devices and/or portable USB-drives, another option is to adapt
Hdparm#Persistent configuration using udev rule
to issue a
--security-freeze
for all drives (incl. HDD).
Hardware encryption
As noted in
#Frozen mode
, 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 errors in the
journal
look like:
ata9: exception Emask 0x0 SAct 0xf SErr 0x0 action 0x10 frozen
ata9.00: failed command: READ FPDMA QUEUED
ata9.00: cmd 60/04:00:d4:82:85/00:00:1f:00:00/40 tag 0 ncq 2048 in
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
boot loader
configuration. To disable NCQ only for disk 0 on port 9 use:
libata.force=9.00:noncq
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 or Crucial M550 SSDs) are failing with certain SATA controllers when
SATA Active Link Power Management (ALPM)
, is enabled.
ALPM is enabled by default since linux-4.16, or may be enabled at runtime by a power saving daemon (e.g.
TLP
,
Laptop Mode Tools
). See
Power management#SATA Active Link Power Management
for more on this.
External SSD with TRIM support
This article or section needs language, wiki syntax or style improvements. See
Help:Style
for reference.
Reason:
Several
style
and formatting problems, especially too many explicit commands - see
Help:Style#File editing requests
. (Discuss in
Talk:Solid state drive
)
This article or section needs expansion.
Reason:
The path for geting vendor and product IDs from /sys/block/ is not fully specified. (Discuss in
Talk:Solid state drive#More_specific_path_in_/sys/block/_to_get_idVendor_and_idProduct
)
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/sd
X
, you can find out whether that is the case by using the command from
sg3_utils
:
# sg_readcap -l /dev/sd
X
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/sd
X
Look for lines in the output that look like this:
Logical block provisioning VPD page (SBC)
  LBPU=1
  LBPWS=0
  LBPWS10=0
This example would tell you the device supports the "UNMAP" command.
Have a look at the output of
$ cat /sys/block/sd
X
/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/sd
X
/device/scsi_disk/*/provisioning_mode
This should immediately enable you to use tools like
blkdiscard
on
/dev/sd
X
or
fstrim
on file systems mounted on
/dev/sd
X
.
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/sd
X
/../../../../../../idVendor
$ cat /sys/block/sd
X
/../../../../../../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
lsusb
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.
To check your current firmware version:
# smartctl -i /dev/
ssd_device
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.
Warning
It is discouraged to attempt to update firmware through
Wine
as it is not designed to handle hardware interfaces and an incomplete firmware update can potentially brick your device.
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. Install
syslinux
and run
isohybrid path/to/image.iso
.
Owners of an M4 Crucial model, may check if a firmware upgrade is needed with
smartctl
.
$ smartctl --all /dev/sd
X
==> WARNING: This drive may hang after 5184 hours of power-on time:
https://www.tomshardware.com/news/Crucial-m4-Firmware-BSOD,14544.html
See the following web page for firmware updates:
https://www.crucial.com/usa/en/support-ssd
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.
Besides the bootable ISO,
micron-storage-executive-cli
AUR
is a command-line tool for flashing firmwares and also offers additional SSD information.
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
intel-mas-cli-tool
AUR
.  There is a
PDF user guide
available.
An example for checking the firmware status is:
# intelmas show -intelssd 0
DevicePath : /dev/nvme0n1
DeviceStatus : Healthy
Firmware : 002C
FirmwareUpdateAvailable : The selected Intel SSD contains current firmware as of this tool release.
-intelssd 0
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
intelmas load -intelssd 0
. 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,
kingston_fw_updater
AUR
.
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
ocz-ssd-utility
AUR
,
ocztoolbox
AUR
and
oczclout
AUR
.
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
samsung_magician-consumer-ssd
AUR
. Magician only supports Samsung-branded SSDs; those manufactured by Samsung for OEMs (e.g., Lenovo) are not supported.
Note
Samsung does not make it obvious at all that they actually provide these. They seem to have 4 different firmware update pages and each references different ways of doing things.
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
[11]
for more details. Note that this blog post details creating a bootable USB drive with Master Boot Record (
MBR
) that some newer motherboards, e.g.
Intel NUC
no longer support.
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.
Note
Some ISO images will lack the
initrd
Linux image mentioned below. See
#Older SSDs
instead.
Extract the
initrd
Linux image from the ISO image:
$ bsdtar xf
samsung_ssd_firmware
.iso initrd
Extract
root/fumagician/
. This directory contains the firmware update files:
$ bsdtar xf initrd root/fumagician
Finally, run
root/fumagician/fumagician
with root privileges and
reboot
your system (if the firmware was successfully updated).
If after reboot the firmware version does not change, run
root/fumagician/fumagician 2> log
and search for errors in the log file. For example, if the log shows 'unzip is not available', install unzip or extract it from the initrd.
Older SSDs
Some of the SSD firmware ISO images contain a FreeDOS image instead of an
initrd
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
BTDSK.IMG
SSR/
840
isolinux/btdsk.img
samsung/DSRD/
840 EVO (mSATA), Pro
ISOLINUX/BTDSK.IMG
First, extract the FreeDOS image from the ISO image:
$ bsdtar xf
samsung_ssd_firmware
.iso
freedos_image_path
Mount the FreeDOS image to
/mnt/
:
# 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
magician --list
(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
/boot
partition and boot them with
GRUB
or
Syslinux
to update the firmware.
See also:
SanDisk Extreme SSD
Manual Firmware update version R211
SanDisk Ultra SSD
Manual Firmware update version 365A13F0
SanDisk Ultra+ SSD
Manual Firmware update version X2316RL
- use
smartctl -i dev/disk/by-id/*SanDisk!(*part*)
as root to determine if a "H2" or "HP" model is used.
See also
Discussion on Reddit about installing Arch on an SSD
Re: Varying Leafsize and Nodesize in Btrfs
Re: SSD alignment and Btrfs sector size
Erase Block (Alignment) Misinformation?
Is alignment to erase block size needed for modern SSD's?
Btrfs support for efficient SSD operation (data blocks alignment)