Solid state drive/NVMe
NVM Express (NVMe) is a specification for accessing SSDs attached through the PCI Express bus. As a logical device interface, NVM Express has been designed from the ground up, capitalizing on the low latency and parallelism of PCI Express SSDs, and mirroring the parallelism of contemporary CPUs, platforms and applications.
The Linux NVMe driver is natively included in the kernel since version 3.3. NVMe devices should show up under
Extra userspace NVMe tools can be found inor AUR.
See Solid State Drives for supported filesystems, maximizing performance, minimizing disk reads/writes, etc.
List all the NVMe SSDs attached with name, serial number, size, LBA format and serial:
# nvme list
List information about a drive and features it supports in a human-friendly way:
# nvme id-ctrl -H /dev/nvme0
List information about a namespace and features it supports:
# nvme id-ns /dev/nvme0n1
Output the NVMe error log page:
# nvme error-log /dev/nvme0
Delete a namespace:
# nvme delete-ns /dev/nvme0n1
Create a new namespace, e.g creating a smaller size namespace to overprovision an SSD for improved endurance, performance, and latency:
# nvme create-ns /dev/nvme0
nvme help and for a list of all commands along with a terse description.
Output the NVMe SMART log page for health status, temp, endurance, and more:
# nvme smart-log /dev/nvme0
-Hoption to output even more information, e.g.
nvme smart-log -H /dev/nvme0.
Currently implemented features (as taken from the wiki):
- Basic information about controller name, firmware, capacity (
- Controller and namespace capabilities (
- SMART overall-health self-assessment test result and warnings (
- NVMe SMART attributes (
- NVMe error log (
smartctl -l error[,NUM])
- Ability to fetch any nvme log (
smartctl -l nvmelog,N,SIZE)
- The smartd daemon tracks health (
-H), error count (
-l error) and temperature (
Firmware can be managed using. To display available slots and check whether Slot 1 is read only:
# nvme fw-log /dev/nvme0
Firmware Log for device:nvme0 afi : 0x11 frs1 : 0x32303132345a3553 (S5Z42102) frs2 : 0x32303132345a3553 (S5Z42102)
# nvme id-ctrl /dev/nvme0 -H | grep Firmware
[0:0] : 0 Firmware Slot 1 Read/Write
Download and commit firmware to specified slot. In the example below, firmware is first committed without activation (
-a 0). Next, an existing image is activated (
-a 2). Refer to the NVMe specification for details on firmware commit action values.
# nvme fw-download -f S5Z42_fw_S5Z42105.bin /dev/nvme0
Firmware download success
# nvme fw-commit -s 2 -a 0 /dev/nvme0
Success committing firmware action:0 slot:2
# nvme fw-log /dev/nvme0
Firmware Log for device:nvme0 afi : 0x21 frs1 : 0x32303132345a3553 (S5Z42102) frs2 : 0x35303132345a3553 (S5Z42105)
# nvme fw-commit -s 2 -a 2 /dev/nvme0
Success committing firmware action:2 slot:2
Finally reset the controller to load the new firmware
# echo 1 > /sys/class/nvme/nvme0/reset_controller
"The Intel® Memory and Storage Tool (Intel® MAS) is a drive management tool for Intel® SSDs and Intel® Optane™ Memory devices, supported on Windows*, Linux*, and ESXi*. [...] Use this tool to manage PCIe*-/NVMe*- and SATA-based Client and Datacenter Intel® SSD devices and update to the latest firmware."
Install AUR and check whether your drive has an update available:
# intelmas show -intelssd
- Intel SSD 660p Series redacted - Capacity : 512.11 GB CurrentPercent : Property not found DevicePath : /dev/nvme0n1 DeviceStatus : Healthy Firmware : 002C FirmwareUpdateAvailable : 004C Index : 0 MaximumLBA : 1000215215 ModelNumber : INTEL SSDPEKNW512G8 ProductFamily : Intel SSD 660p Series SMARTEnabled : True SectorDataSize : 512 SerialNumber : redacted
If so, execute the
load command as follows:
# intelmas load -intelssd 0
WARNING! You have selected to update the drives firmware! Proceed with the update? (Y|N): Y Checking for firmware update... - Intel SSD 660p Series redacted - Status : Firmware updated successfully. Please reboot the system.
Kingston does not provide separate firmware downloads on their website, instead referring users to a Windows only utility. Firmware files appear to use a predictable naming scheme based on the firmware revision:
Then proceed with the generic flashing instructions.
NVMe SSDs are known to be affected by high operating temperatures and will throttle performance over certain thresholds.
Raw device performance tests can be run with:
# hdparm -Tt --direct /dev/nvme0n1
Power Saving (APST)
To check NVMe power states, install
nvme get-feature /dev/nvme[0-9] -f 0x0c -H:
# nvme get-feature /dev/nvme0 -f 0x0c -H
get-feature:0xc (Autonomous Power State Transition), Current value:0x000001 Autonomous Power State Transition Enable (APSTE): Enabled Auto PST Entries ................. ...
When APST is enabled the output should contain "Autonomous Power State Transition Enable (APSTE): Enabled" and there should be non-zero entries in the table below indicating the idle time before transitioning into each of the available states.
If APST is enabled but no non-zero states appear in the table, the latencies might be too high for any states to be enabled by default. The output of
nvme id-ctrl /dev/nvme[0-9] (as the root user) should show the available non-operational power states of the NVME controller. If the total latency of any state (enlat + xlat) is greater than 25000 (25ms) you must pass a value at least that high as parameter
default_ps_max_latency_us for the
nvme_core kernel module. This should enable APST and make the table in
nvme get-feature (as the root user) show the entries.
Controller failure due to broken APST support
Some NVMe devices may exhibit issues related to power saving (APST). This is a known issue for Kingston A2000  as of firmware S5Z42105 and has previously been reported on Samsung NVMe drives (Linux v4.10) 
A failure renders the device unusable until system reset, with kernel logs similar to:
nvme nvme0: I/O 566 QID 7 timeout, aborting nvme nvme0: I/O 989 QID 1 timeout, aborting nvme nvme0: I/O 990 QID 1 timeout, aborting nvme nvme0: I/O 840 QID 6 timeout, reset controller nvme nvme0: I/O 24 QID 0 timeout, reset controller nvme nvme0: Device not ready; aborting reset, CSTS=0x1 ... nvme nvme0: Device not ready; aborting reset, CSTS=0x1 nvme nvme0: Device not ready; aborting reset, CSTS=0x1 nvme nvme0: failed to set APST feature (-19)
As a workaround, add the kernel parameter
nvme_core.default_ps_max_latency_us=0 to completely disable APST, or set a custom threshold to disable specific states.
# smartctl -a /dev/nvme0
Supported Power States St Op Max Active Idle RL RT WL WT Ent_Lat Ex_Lat 0 + 9.00W - - 0 0 0 0 0 0 1 + 4.60W - - 1 1 1 1 0 0 2 + 3.80W - - 2 2 2 2 0 0 3 - 0.0450W - - 3 3 3 3 2000 2000 4 - 0.0040W - - 4 4 4 4 15000 15000
The value passed is the maximum exit latency (Ex_Lat). For example, to disable PS4 set