New rMBP SSD write speed getting slower

Discussion in 'MacBook Pro' started by benjaminzsj, Dec 30, 2012.

  1. benjaminzsj macrumors newbie

    Joined:
    Dec 30, 2012
    #1
    Hi all,

    I have been using my new baseline model 15" rMBP for a week now. When I first got it, I used Blackmagic speed test and got pretty good results, 400+ for both write and read. But now when I did the same test, the write speed is much slower, around 200, read speed is about the same though. Shutdown and startup speed seems slower as well but I am not sure, speed of running applications does not seems slow maybe because it's still pretty fast compared to a HDD.

    Is this normal wear and tear or is there actually something wrong with the drive? During the week, I downloaded some files, small and big, now the free space on the drive is around 135GB, installed a VM in Parallels, enabled Time Machine. I also encrypted the drive using FileVault 2.

    Thanks.
     
  2. krravi macrumors 65816

    Joined:
    Nov 30, 2010
    #2
    Did you encrypt the drive recently? Did you do the first test with or without encryption?

    Either way encryption is the culprit. Unless you have very sensitive documents to be protected in case of theft... disable encryption for performance.
     
  3. CausticPuppy macrumors 65816

    Joined:
    May 1, 2012
    #3
    From what I've read, the Toshiba SSD's are pretty bad when it come to performance on FileVault encrypted drives, but the Samsung SSD's handle it much better.
     
  4. AirThis macrumors 6502a

    Joined:
    Mar 6, 2012
    #4
    I've Filevaulted mine. I get 455 read, 435 write with a Samsung SSD. Without encryption the numbers are practically identical.

    I suggest that you decrypt your drive to see if that's the culprit. It only takes a couple of hours to do.
     
  5. benjaminzsj thread starter macrumors newbie

    Joined:
    Dec 30, 2012
    #5
    I just disabled FileVault and the speed is back to normal, so it was the FileVault that's causing the slowdown.

    AirThis, are you using Mountain Lion?
     
  6. AirThis macrumors 6502a

    Joined:
    Mar 6, 2012
    #6
    Yes. I'm using ML.

    As CausticPuppy said above, there are 2 different SSDs brands shipped with the rMBP. I think you might have a Toshiba, which doesn't handle encryption so well. Check your system info.
     
  7. benjaminzsj thread starter macrumors newbie

    Joined:
    Dec 30, 2012
    #7
    My SSD model number is APPLE SSD SD256E, which is from SanDisk.

    I really hope there is something I can do to mitigate this problem without turning off FileVault.
     
  8. genoso macrumors newbie

    Joined:
    Apr 6, 2013
    #8
    Did you manage to solve the performance problem with Filevault 2 enabled? I am suffering same issue and it is really frustrating
     
  9. ventmore macrumors 6502

    Joined:
    Jul 13, 2008
    #9
    I am experiencing the same as you guys. I have the 512GB Sandisk, and before Filevault, I was seeing 400 writes, and 470 reads using Black Magic speed test.

    After Filevault, I'm seeing 450 reads, but the writes are inconsistent. I've seen as high as 350, and as low as 120.

    Doing a file transfer test to and from a ramdisk confirmed the inconsistent writes.

    Startup and shutdown times are unaffected, and the machine seems to be running as quickly as ever, so I suspect, if I hadn't benchmarked it, I wouldn't have noticed the difference.

    Bottom line......stop benchmarking, and start enjoying your machine! :)
     
  10. genoso macrumors newbie

    Joined:
    Apr 6, 2013
    #10
    Filevault speed reduction with sandisk

    In my case I noticed the speed decreased and now I am back to unencrypted disk. When encrypted, speed is still much faster than a regular mechanical HD, but my feeling is it is not as fast. Notice the effect is on writes, not on reading, so booting OS is not an example of speed degradation

    I took my laptop to an apple store and they kept there for a couple of days, but since their tests does not measure HD speed but physical errors, they return it to me without any action :-(
     
  11. ventmore macrumors 6502

    Joined:
    Jul 13, 2008
    #11
    I'm going to just run mine for a while. If I notice any slowdowns with the day to day running, then I'll weigh up the speed loss against the security of my data.

    I realise it's the write speed taking the hit......I only mentioned the startup because the OP felt his machine wasn't staring up as quickly :)
     
  12. kosekmi macrumors newbie

    Joined:
    Jul 25, 2013
    #12
    Hey guys,
    i am experiencing the same problem, except that i am not using filevault.
    for testing purposes i encrypted my disk, speed tested, and decrypted it: the write speeds are the same (about 230-250).
    any suggestions?
     
  13. nickandre21 macrumors 6502a

    Joined:
    Jun 21, 2012
    #13
    yes encryption does make the hard drive slower, this is what my service center said,"it will cause slower boot up and shut down speeds" they also said that if my files were needed daily then its ok but if not i should transfer them onto an external hard drive and encrypt it.
     
  14. kosekmi macrumors newbie

    Joined:
    Jul 25, 2013
    #14
    i forgot to mention that i dont want to use filevault or any kind of encryption. the problem is that i am getting the same slow speed using filevault or not.
     
  15. jav6454 macrumors P6

    jav6454

    Joined:
    Nov 14, 2007
    Location:
    1 Geostationary Tower Plaza
    #15
    Slower write speeds are expected of a SSD as time goes by. Unluckily OS X lacks the garbage collection activities Windows has in place.
     
  16. robvas macrumors 68020

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    Mar 29, 2009
    Location:
    USA
    #16
    That's simply not true - OS X has TRIM.
     
  17. alex0002 macrumors 6502

    Joined:
    Jun 19, 2013
    Location:
    New Zealand
    #17
    What do you mean by.... OS X lacks the garbage collection activities?

    Garbage collection takes place in the SSD according the instructions in SSD firmware and the operating system just sees a range of logical blocks. However, the SSD controller remaps the logical block <--> NAND page relationship, cleans unused pages and ensures that free pages are available for use. That is garbage collection and is independent of the operating system.

    Or did you have some other sort of garbage collection in mind?

    Now TRIM requires support from the operating system, but OS X has that too.
     
  18. lagisibuk macrumors 6502

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    Jun 25, 2013
    Location:
    Always Somewhere
    #18
    I'm using 15 retina with sandisk SSD 256GB
    for W=417 and R=462

    I have been using for 6 month :)
     
  19. jav6454 macrumors P6

    jav6454

    Joined:
    Nov 14, 2007
    Location:
    1 Geostationary Tower Plaza
    #19
    Just TRIM... not enough.

    OS X only has TRIM, other SSDs have some OS level garbage collection algorithms that can be supported. Apple isn't best when it comes to implementing SSD controls.

    That is why the Samsung 840 SSD is best for Macs (last I checked SSDs) as it is self cleaning and has best speeds after months of average usage.
     
  20. genoso macrumors newbie

    Joined:
    Apr 6, 2013
    #20
    Hi again,

    I manage to buy a 768 SAMSUNG SSD Blade for the retina MBP and it is completely differendt than Sandisk unit, now I have FILEVAULT 2 encryption and write speed remains constant as read speed at 435 MB/s, so I confirm it is a problem with the 256 GB units with sand force controller

     
  21. robvas macrumors 68020

    Joined:
    Mar 29, 2009
    Location:
    USA
    #21
    Sandforce only hits peak writes on compressible data - encrypted data is very similar in compression rates to random data, so those drives will have lower performance. This has been known for a quite a while.

    More info here:

    http://www.anandtech.com/show/6063/macbook-air-13inch-mid-2012-review/4
     
  22. CausticPuppy macrumors 65816

    Joined:
    May 1, 2012
    #22
    Alright, since my rMBP has a Samsung drive I finally enabled Filevault today. Took about 10 minutes to encrypt 35GB of data. Way faster than I expected.

    I have noticed zero difference in usage, but I didn't run benchmarks.... if there's no noticeable difference what's the point in getting hung up on synthetic benchmarks?

    Still boots in under 10 seconds (after entering the password which shows up at the beginning now). Apps still load blisteringly fast. No cpu hit that I can tell.

    The only change is how the guest account works, there's no fast user switching to the guest account- it must reboot to a Safari-only partition with a nice linen background.

    If somebody enabled filevault and didn't tell me, I would have never suspected anything based on just using the system. :)
     

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