Enable iostat support for Micron drives


#1

Summary:

The Linux driver for Micron drives contains an internal parameter that disables support for iostat and Micron drives thus do not show up on iostat. To re-enable iostat, following steps are required.

Resolution:

  1. Download the latest support pack. The driver name is mtip32xx. Run the following to determine the name of the driver (reference as <driver_name> in the instructions below).

        $ lsmod | grep mti*
    
  2. Log in as root. Root access is required. If you do not have root access, enable access by the following: a) Enter the following command:

         $ /lib/modules/`uname -r`/extra/<driver_name>/<driver_name>.ko
    

    b) Run the following to adjust write permissions.

         $ chmod 777<driver_name>.ko
    
  3. Install the latest Linux driver from the support pack following the standard instructions. After installation, follow these steps: a) Verify the driver name following step 1 in this section. b) Run the following and confirm the output

         $ fdisk -| // output should be /dev/rssda
    
  4. Uninstall the driver and reinstall the driver with stats flag enabled: a) Enter the following command:

        $ modprobe -r <driver_name>
    

    b) And then this

        $ insmod /lib/modules/`uname-r`/extra/<driver_name>/<driver_name>.ko stats=1
    
  5. Run som I/O on the drive using any I/O stress took such as FIO or Vdbench. During this time, run one of the following commands.

        $ cat /proc/diskstat 
    

    or

        $ cat /sys/block/rssda/stat
    
  6. Verify the diskstat counts for rssd or stat output are being populated.