rMBP write speeds slow down?

Discussion in 'MacBook Pro' started by Mr.Skynet, Nov 20, 2014.

  1. Mr.Skynet macrumors newbie

    Mr.Skynet

    Joined:
    Mar 3, 2014
    #1
    I just did a fresh install of OS X Yosemite and after I installed all my apps, my write speeds have dropped to 342 MB/s when the computer should be putting out about 712 MB/s. What the hell happened? This computer isn't even a year old yet and it slows down this much? Any suggestions? :mad:
     
  2. Samuelsan2001 macrumors 604

    Joined:
    Oct 24, 2013
    #2
    Have you loaded back some data?

    If you have loaded back a lot of data it could be spotlight indexing this will interfere with blackmagic speed test.
     
  3. Weaselboy Moderator

    Weaselboy

    Staff Member

    Joined:
    Jan 23, 2005
    Location:
    California
    #3
    Do a command-s boot to single user mode then enter "fdisk -fy" (without the quotes) at the command prompt. That will TRIM all unused blocks on the SSD and hopefully get your write speeds back to like new.
     
  4. Mr.Skynet thread starter macrumors newbie

    Mr.Skynet

    Joined:
    Mar 3, 2014
    #4
    That might have contributed, however I noticed that I enabled the FileVault encryption when I reinstalled and that was killing it! Disabled and now its back to normal. Thanks for replies guys! :)
     
  5. Weaselboy Moderator

    Weaselboy

    Staff Member

    Joined:
    Jan 23, 2005
    Location:
    California
    #5
    FV does slow it a bit, but should not by the one half you are reporting. So you did a speed test before and after FV and it went from 712 to 342 write speeds?
     
  6. cjmillsnun macrumors 68020

    Joined:
    Aug 28, 2009
    #6
    I have FV enabled and get this...

    I suspect your issue is more down to something else.
     

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  7. Mr.Skynet thread starter macrumors newbie

    Mr.Skynet

    Joined:
    Mar 3, 2014
    #7
    It's not that its slowing them down. When I did the speed test and got the low write speeds, it was because it was currently encrypting the drive while I performed the test. As soon as I finished the encryption the speeds went back to normal.
     
  8. cjmillsnun macrumors 68020

    Joined:
    Aug 28, 2009
    #8
    That makes more sense. So in effect the disk was busy.
     
  9. Weaselboy Moderator

    Weaselboy

    Staff Member

    Joined:
    Jan 23, 2005
    Location:
    California
    #9
    Oh heck yeah... that would kill a speed test. :)

    So speeds are back to normal now?

    Glad you are fixed up. FV encryption is a really great feature and the first thing I do on any new Mac.
     

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