[arch-general] Samsung NVMe set up

[Alan E. Davis]

Hello everyone:

I built a new machine with a Samsung SSD 960 EVO NVMe
<https://www.googleadservices.com/pagead/aclk?sa=L&ai=DChcSEwjWxp_rk8nUAhWBfn4KHadiANoYABABGgJwYw&ohost=www.google.com&cid=CAESEeD2DLyQ7hEOLOBgSPqc9iEd&sig=AOD64_35gPrHU2xXVzC269PD9qfp0UjlwQ&ctype=5&q=&ved=0ahUKEwi6nZrrk8nUAhUE42MKHXAuDBsQww8ILA&adurl=>Samsung
SSD 960 EVO NVMe
<https://www.googleadservices.com/pagead/aclk?sa=L&ai=DChcSEwjWxp_rk8nUAhWBfn4KHadiANoYABABGgJwYw&ohost=www.google.com&cid=CAESEeD2DLyQ7hEOLOBgSPqc9iEd&sig=AOD64_35gPrHU2xXVzC269PD9qfp0UjlwQ&ctype=5&q=&ved=0ahUKEwi6nZrrk8nUAhUE42MKHXAuDBsQww8ILA&adurl=>Samsung
950 EVO NVMe M.2 500GB component.  Installation went swell.  I was able to
use bootctl (by whatever name), which seemed to be easier than using GRUB.
(on the Manjaro wiki was found an extremely coherent discussion of this
system).  I have encountered no problems other than slow-ish (if one would
call it that).

When I run hdparm to test the performance of this memory, it falls far
short of the specification of 32 Gb/s.  I realize that the Linux kernel has
recently included some code for the NVME drivers.  There is also some
question as to the best parameters to use in /etc/fstab.



So I am requesting assistance to set up this device on this mailing list.

I am using the Zen kernel.  Some checks I have made:


# hdparm -Tt --direct /dev/nvme0n1

/dev/nvme0n1:
 Timing O_DIRECT cached reads:   2404 MB in  2.00 seconds = 1201.67 MB/sec
 Timing O_DIRECT disk reads: 5372 MB in  3.00 seconds = 1790.16 MB/sec



#  nvme get-feature -f 0x0c -H /dev/nvme0n1p2
get-feature:0xc (Autonomous Power State Transition), Current value:0x000001
        Autonomous Power State Transition Enable (APSTE): Enabled
        Auto PST Entries        .................
        Entry[ 0]
        .................
        Idle Time Prior to Transition (ITPT): 86 ms
        Idle Transition Power State   (ITPS): 3
        .................
        Entry[ 1]
        .................
        Idle Time Prior to Transition (ITPT): 86 ms
        Idle Transition Power State   (ITPS): 3
        .................
        Entry[ 2]
        .................
        Idle Time Prior to Transition (ITPT): 86 ms
        Idle Transition Power State   (ITPS): 3
        .................
        Entry[ 3]
        .................
        Idle Time Prior to Transition (ITPT): 410 ms
        Idle Transition Power State   (ITPS): 4


Alan Davis

-- 
[I do not] carry such information in my mind since it is readily
available in books. …The value of a college education is not the
learning of many facts but the training of the mind to think.
          ---Albert Einstein



"Sweet instruments hung up in cases. . . keep their sounds to themselves."

         ---Shakespeare, _Timon of Athens_