Does my read/write speed seem off?

Discussion in 'Mac Basics and Help' started by thefknmtns, Mar 25, 2017.

  1. thefknmtns macrumors newbie

    Mar 25, 2017
    I recently purchased a 2012 MacBook Pro 15" (2.3ghz/8gb/hi res) and it came with a Samsung 850 Evo 1tb SSD. I used a boot drive from my old 2010 MacBook Pro 13" with macOS Sierra to install onto the new laptop. Just checking my SSD speeds via Blackmagic on the fresh install of Sierra (on the 15") I get around 250 write speed and around 500 read speed. Does this seem right? I feel like maybe my write speed is off?

    As a reference, my old 2010 MBP 13" (running El Cap) has a Samsung 850 Evo 250gb SSD and gets ~200 write and 250 read.

    Knowing the 2012 uses SATA III, and the 2010 uses SATA II.. would this be a hardware issue I'm possibly having on the newer laptop? Or maybe just software?

    Thanks in advance
  2. Fishrrman macrumors G5


    Feb 20, 2009
    Read speeds will typically be faster than write speeds when running on SATA SSDs.

    Often, the write speeds will vary, depending on the drive's size, the particular drive model, etc. (while the read speeds will be more constant).

    The speeds you're getting seem fine to me.
  3. Weaselboy Moderator


    Staff Member

    Jan 23, 2005
    Yeah... that's kinda slow. You should see around 400 or os. It may be TRIM was never enabled to the write speeds have suffered. Try this. Open Terminal and enter the line below the enable TRIM (it will reboot).

    sudo trimforce enable
    Now reboot again and hold command-s to boot to single user mode. Then at the command prompt, run this command. Toward the end of the run you should see a message something like trimming unused blocks.

    fsck -fy
    Then type in reboot to restart and test again.

Share This Page