SSD - Ways to lower writes to disc (LBA)

Discussion in 'MacBook Pro' started by MacUse-R, Mar 18, 2018.

  1. MacUse-R macrumors member

    Joined:
    Dec 24, 2017
    #1
    What ways are there to lower the writes to the SSD disk (LBA´s written)?
    I have heard that some functions turned on can write a considerable amount of data to the disk.

    I have already turned off the safe sleep mode.
    How about journaling, how does that work, does journaling write anything regularly to the SSD / hard drive?

    I would appreciate some tips and tools on functions that writes a not too small of an amount of data to the SSD and which can be disabled?

    I´m using a MacBook Pro late 2011 with a 512GB SSD as primary boot drive, and a second 2TB Harddrive in the optical drive bay.
     
  2. Toutou macrumors 6502a

    Toutou

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    Prague, Czech Republic
    #2
    Is there something wrong with your SSD? I believe macOS's disk usage is rather conservative.
     
  3. Samuelsan2001 macrumors 604

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    Oct 24, 2013
    #3
    Modern SSD's can write Petabytes of data to disk before suffereing any ill effects unless you are writing literally Terabytes of data a day it will be fine.
     
  4. alex_at, Mar 19, 2018
    Last edited: Mar 19, 2018

    alex_at macrumors newbie

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    Mar 19, 2018
    #4
    despite of the fact that modern SSD's can handle much more writes than ever before, I personally like to minimize unneccesary writes - just like MacUse-R.

    Even on my 2015 15" where I recently upgraded from my stock 256gb to a 960gb Transcend Jetdrive 820. I would definetly do it on 2016 and newer MBP's where the SSD is soldered on.

    I do/did as following:

    • I don't use hibernation - if needed I use sleep (but I even don't use sleep much since I'm not a fan of the idea of leaving the soldered on non replaceable ram under constant use if not necessary.)

    • For "non valuable" data such as Downloads for example I store them either on my NAS connected per Samba (which is plenty fast enough for those tasks) - or if I'm on the go I use a Nifty Drive or an SD Card. But 99,9% of the time my MBP stays at home at the desk.
    • I used a symbolic link to "relocate" the temporary files of quicktime player to my NAS - no need to write that on my SSD.
    • The most important step (for my use) is I disabled the Firefox History, gave Firefox more Ram to use and disabled disk cache and other - for my scenario - unnecessary disk write operations.

    • I dont need local backups of my iPhone or iPad Pro on my Macbook, I have iCloud for that.
    • I don't run Spotlight - I am pretty organized with my files so I usually know where to look for what I want to find

    By doing so I can lower the amount of GB written to only a few gb per session.

    I dont need local backups of my iPhone or iPad Pro on my Macbook, I have iCloud for that.

    I can update with the settings in Firefox when I come home - possibly there are more things that I cant remember at the moment.
     
  5. PBG4 Dude macrumors 68030

    PBG4 Dude

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    Jul 6, 2007
    #5
    @alex_at You realize your iCloud documents are also stored in a Mobile Documents folder in ~/Library/Application Support, right? Because it doesn’t sound like you know this.
     
  6. alex_at macrumors newbie

    Joined:
    Mar 19, 2018
    #6
    @PBG4 Dude

    No I didn't know exactly, but I suspected that icloud documents get at least temporarily stored somwhere locally...

    But what I store in my icloud - in terms of amount of data will likely never ever be enough to harm the ssd writes in any way .....
     
  7. Toutou macrumors 6502a

    Toutou

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    #7
    And this is where you're absolutely right and the reason why you're probably wasting your time doing all that. Not only "much more writes than ever before" - they can handle an absurd number of writes. You could use your MacBook as a cloud storage server and you probably wouldn't even come close to the amount of writes that thing is capable of.
    At this moment, I would be more concerned about a HDD than an SSD. HDDs are actually very fragile and deteriorate mechanically.
     
  8. Fishrrman macrumors P6

    Fishrrman

    Joined:
    Feb 20, 2009
    #8
    You could turn off Spotlight -- easily done.

    You could TRY turning off virtual memory paging to disk (in and out).
    It might work, so long as you don't overload the RAM by keeping too many programs/windows open at one time.
     
  9. alex_at macrumors newbie

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    Mar 19, 2018
    #9
    Good idea, one of the first things I did.
     
  10. DeltaMac macrumors G3

    DeltaMac

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    Jul 30, 2003
    Location:
    Delaware
    #10
    This thread makes me curious, so I have a question: What is the process that you go through to decide which writes are "unnecessary"?
    Some folks here would say that manually limiting writes to an SSD is also unnecessary, ultimately a waste of your time, at least with current tech.
     
  11. Samuelsan2001 macrumors 604

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    Oct 24, 2013
    #11
    Most folks here would say that to be honest...
     
  12. Gaura Mohana macrumors regular

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    Feb 24, 2011
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    Gainesville, FL
    #12
    Yeah, seems like the kind of thing you care about if you have nothing better to do in life.
     
  13. MacUse-R, Mar 20, 2018
    Last edited: Mar 20, 2018

    MacUse-R thread starter macrumors member

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    Dec 24, 2017
    #13
    Thanks for your answer. I dont use Firefox at least not yet, so that would be no problem.

    How do you disable spotlight, or do you just not use it?

    And how do you make the symbolic link thing for the temp,files? Is that function saving you from much writings to the SSD?

    I have a second HDD drive installed in the optical drive bay, i was thinking if it is a good idea to put the home folder on the second HDD drive instead of on the primary SSD drive?
    That way most files would be stored and downloded to the HDD instead of the SSD?
    I guess maybe the Apolication folder could be stored on the SSD for fast startups of programs?
    Is there any drawbacks to doing it like that?

    I guess that is much like you are doing but instead of a NAS i will use the second HDD drive on the MacBook Pro?
    --- Post Merged, Mar 20, 2018 ---
    Or maybe one is smart and want ones SSD to last as long as possible.
    If ones SSD is writing 30GB a day and one can pretty easily get it down to 3 GB or less per day why would one not do it?
    Why would one not try to limit the wear on the SSD?

    It seems YOU have nothing better to do in life if you have time to write these totally unessecery and unhelpful posts?
    --- Post Merged, Mar 20, 2018 ---
    Well if you look at the manufacturers guaranteed TBW it doesnt sound so increadibly much.
    Sure most SSD's will probobly handle more than the manufacturer specified amount, but im thinking if SSD's could handle such an absurd amount of data written to it why would they not have a higher TBW limit?
    --- Post Merged, Mar 20, 2018 ---
    Well writings that comes from functions that i dont need is what i consider unecessery writings.

    And the thing about waste of time, since you only do these things one time to limit the amount of written data i dont know how much actual time you waste?
     
  14. Fishrrman macrumors P6

    Fishrrman

    Joined:
    Feb 20, 2009
    #14
    OP asked:
    "How do you disable spotlight, or do you just not use it?"

    This turns off spotlight:
    sudo mdutil -a -i off

    This removes the existing spotlight index:
    sudo rm -rf /.Spotlight-V100/*

    You could also turn off hibernation mode.
    (4 step process)

    1. Turn off hibernation itself:
    sudo pmset -a hibernatemode 0

    2. Remove existing sleep image:
    sudo rm /Private/var/vm/sleepimage

    3. Next, create a new (empty) sleep image:
    sudo touch /Private/var/vm/sleepimage

    4, Finally, change the flags on the new image so it can't be re-written:
    sudo chflags uchg /Private/var/vm/sleepimage

    This should turn off VM disk swapping:
    sudo launchctl unload -w /System/Library/LaunchDaemons/com.apple.dynamic_pager.plist

    Then, remove the VM swap file:
    sudo rm /private/var/vm/swapfile*

    Finally, check that VM is disabled:
    sysctl vm.swapusage

    If VM is off, report should be:
    vm.swapusage: total = 0.00M used = 0.00M free = 0.00M

    Restart required after doing the above.
     
  15. MacUse-R thread starter macrumors member

    Joined:
    Dec 24, 2017
    #15
    Thanks for the clear instructions, i will try them and see how much lower the writes gets.

    I read some where about some people moving their Home folders to the second HDD instead of keeping it on the primary SSD drive, dont know if that is a smart move though?
    I think its good to have at least the applications folder on the SSD.
    Some of the other folders for example music, downloads, movies etc. i guess one can create those folders on the second HDD and point downloads to those folders?
     
  16. Ries macrumors 68020

    Joined:
    Apr 21, 2007
    #16
  17. DeltaMac macrumors G3

    DeltaMac

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    Delaware
    #17
    And, if your goal is to limit writes as much as possible, the majority of writes during system use STILL go to the boot drive. Moving your user folder will change the total to some minor degree, but cache files and many other temporary system usage writes continue to go to the boot volume.
    Try to understand, all things being equal, the SSD (with no moving parts) will, on average, last longer than the spinning rust. The failure of bearings and other moving parts is more likely than the eventual exhaustion of the cells on the typical SSD.
    Your MBPro will likely be on the "scrapheap of death" before the SSD wears out enough to make your manipulation of the system worth doing.
    It's not about that few simple steps that you only do once - it's that your perceived goal of a longer SSD life may not be worth the hassle when it's MORE likely that you would choose to stop writes to the SSD that the system makes use of for enhanced performance, or affects apps in some unintended way.

    You would probably get the most advantage from saving space (if your SSD is relatively small), but preventing as many writes as possible to add maybe less than single-digit per cent total life to your SSD is a noble project, but not particularly valuable for the home user in real life. The rest of your hardware likely won't last as long as the SSD.
     
  18. Fishrrman macrumors P6

    Fishrrman

    Joined:
    Feb 20, 2009
    #18
    OP wrote:
    "I read some where about some people moving their Home folders to the second HDD instead of keeping it on the primary SSD drive, dont know if that is a smart move though?"

    Do not, repeat DO NOT attempt to do this unless you are absolutely certain that you know what you're doing. Make a mistake, and things could go very wrong.

    A better way to handle this would be to leave the home folder (and the primary folders INSIDE the home folder) on the boot drive, but...
    ... move the "large libraries" (such as movies, music, and pics) to another drive.
    These items are easily "referenced" from another drive by the apps that use them.
     
  19. MacUse-R thread starter macrumors member

    Joined:
    Dec 24, 2017
    #19
    But then one also needs to think about that often long before a SSD fails it can start to have bad sectors etc. which the techreport experiment also confirms. So i dont know if one should trust an SSD which starts have a lot of bad sectors and other problems, and if one at that point should continue to use that SSD drive?
    If i remember correctly for example the Samsung 840 started having problems at around 600 TB?
    Just a thought.
     
  20. Toutou macrumors 6502a

    Toutou

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    Location:
    Prague, Czech Republic
    #20
    Bad memory cells are supposed to happen, and there is a mechanism built in that gradually replaces the bad ones with spare ones. The drive is 100% healthy until the first read/write error appears. After that it's no longer safe for critical data.
     
  21. NoBoMac macrumors 68000

    Joined:
    Jul 1, 2014
    #21
    This.

    My SSD is almost 5.5yo now, no issue. The display though, some dead pixels. Trackpad button is sticking a bit. Ditto keyboard. One USB port has some wiggle in it (ie. some USB cables are loose in it). On my fourth battery (probably 5th later this year).
     
  22. simonsi macrumors 601

    simonsi

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    Jan 3, 2014
    Location:
    Auckland
    #22
    Wait, you think using HDD space in order to "save" your SSD is a good thing? Your HDD is literally wearing out with every revolution whether you write, read or do nothing with it...facepalm.
     
  23. Pearl Wisdom macrumors member

    Joined:
    Sep 25, 2009
    #23
    I'm surprised no one has mentioned maxing out your RAM, which would be 16 GB in a MacBook Pro late 2011. This would cut down on all the writing involved with virtual memory swapping. The amount of writing involved with hibernating seems negligible in comparison. I'd just max out the RAM, and not worry so much about anything else. By the time your SSD starts having problems, maybe in a few years, a replacement should be very cheap.
     
  24. MacUse-R thread starter macrumors member

    Joined:
    Dec 24, 2017
    #24
    Yes 16GB RAM memory is my next project, i currently have 8GB.
    I noticed that its always using pretty much all of the RAM memory, like 7.99 GB.
    When i had 4GB in the beginning it also used all of the RAM pretty much all of the time.

    So when i upgrade to 16GB i guess it will be using all of the 16GB all the time as well?
    I guess that is maybe how it should be?
     
  25. DeltaMac macrumors G3

    DeltaMac

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    Delaware
    #25
    I think the idea is - why even have memory if some is not used?
    Your macOS takes care of all that for you -- and that's a Good Thing™
     

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