Crucial M4 garbage collection?

Discussion in 'MacBook Pro' started by Quinoky, Oct 7, 2011.

  1. macrumors regular

    Quinoky

    Joined:
    Sep 18, 2011
    Location:
    Groningen, Netherlands
    #1
    Apologies if this has already been asked, but I couldn't find a good answer so far.

    I am planning to buy a 15" MBP next week, but I am still in doubt about one thing: the SSD. I would like to avoid Sandforce based SSD's because of obvious reasons, so the M4 has caught my attention. The problem is: OS X does not support TRIM. Now, compared to the Sandforce chips, the Marvell controller's garbage collection technology is quite inferior. Looking at AnandTech's graphs, without TRIM, performance could drop to 20MB/s and it will only very slowly recover. In my view, this could eventually cause a lot of performance issues with the M4 on Mac OS X, right? Anyone care to comment on this? Thanks in advance.
     
  2. Moderator emeritus

    Hellhammer

    Joined:
    Dec 10, 2008
    Location:
    Finland
    #2
    You can enable TRIM via TRIM Enabler. Anand's tests are also pretty extreme, I have never seen anyone complaining about a slow modern SSD.
     
  3. thread starter macrumors regular

    Quinoky

    Joined:
    Sep 18, 2011
    Location:
    Groningen, Netherlands
    #3
    Well, you see, the effects of TRIM enabler on SSD's are not really known as far as I know. Various sources actually say it negatively affects the SSD's performance.. So I'm quite reluctant to use it. I suppose there's a reason why Apple disabled TRIM.

    I'm actually quite interested in M4 user experiences here, I really do hope there's nothing to worry about after all.
     
  4. macrumors 601

    GermanyChris

    Joined:
    Jul 3, 2011
    Location:
    Here
    #4
    I have Sandforce and am happy. I have also enabled trim in both 10.6 and 10.7
     
  5. thread starter macrumors regular

    Quinoky

    Joined:
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    #5
    Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_3_5 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8L1 Safari/6533.18.5)

    Let me try to be a little more specific.. Is there anyone who knows how the garbage collection tech on the Marvell works? Is it comparable to Samsung's chip (clean up when SSD is idle)?
     
  6. macrumors P6

    Weaselboy

    Joined:
    Jan 23, 2005
    #6
    All modern SSDs have garbage collection. Based on what we see in test results Sandforce is more aggressive about running it quickly, but at the cost of reduced drive performance with incompressible files.

    I too have a problem with the Anand tests where he hammers a drive to death then when it does not immediately recover from garbage collection he pronounces it unfit for and OS without TRIM. I would like to see a test where the drive is filled up from repeated writes then used for a day or two to see if the GC does recover the performance. I have not seen a test like that yet.

    That said, I have not seen users of newer SSDs in the forums complaining their write performance went to hell after usage. If this were the problem Anand makes it out to be, I suspect the forums would be full of complaints.

    Get whatever drive you think has the best vendor support and compatibility. I would not worry about TRIM.
     
  7. thread starter macrumors regular

    Quinoky

    Joined:
    Sep 18, 2011
    Location:
    Groningen, Netherlands
    #7
    +1

    I suppose if TRIM does not matter in real world usage, the M4 is by far the best bang for the buck out there. Thanks guys. :)
     

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