marv12ca

Q: New Operating System

When you install new operating system, will it replace old operating system without a change from its current storage space?

MacBook Pro with Retina display, iOS 10

Posted on Sep 17, 2016 8:41 AM

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Q: New Operating System

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  • by leroydouglas,

    leroydouglas leroydouglas Sep 17, 2016 8:51 AM in response to marv12ca
    Level 7 (23,578 points)
    Notebooks
    Sep 17, 2016 8:51 AM in response to marv12ca

    Yes

  • by Tesserax,

    Tesserax Tesserax Sep 17, 2016 8:52 AM in response to marv12ca
    Level 9 (54,427 points)
    Wireless
    Sep 17, 2016 8:52 AM in response to marv12ca

    Whenever updating software, whether its an operating system or not, it will always change the devices storage space due to a different size of the new software. It could either increase or decrease the overall total space.

     

    It is always best to first fully backup any critical files, wipe out the existing operating system, and install a new operating system. Then restore the required files.

  • by Allan Jones,

    Allan Jones Allan Jones Sep 17, 2016 8:59 AM in response to marv12ca
    Level 8 (35,151 points)
    iPad
    Sep 17, 2016 8:59 AM in response to marv12ca

    There is a space concern but only during the install sequence. At some point both the old and new OS must exist on the computer so that old and new software components can be compared to determine what gets replaced. The old ones get deleted once the new OS approaches the end of the install process. In the meantime you need disk room for both.

     

    For that reason you must make sure you have sufficient hard drive space before attempting a major OS upgrade, like OS 10.10 to OS10.11. I would not want to install an major OS upgrade without a minimum of 20 GB free space--more is better.

     

    If is possible for a new OS version to be slightly different size than was the old one due to upgraded functions or added new features, but such changes are usually not a significant portion of modern, high-capacity  drives.

  • by BobTheFisherman,

    BobTheFisherman BobTheFisherman Sep 17, 2016 8:59 AM in response to marv12ca
    Level 6 (15,344 points)
    Sep 17, 2016 8:59 AM in response to marv12ca

    It is difficult, at least for me, to understand exactly what you are asking. Will the installation of the new OS re-partition and change the partition size on your drive? No. Will the new OS occupy exactly the same amount of space on your drive as the old OS? No.

  • by kaz-k,

    kaz-k kaz-k Sep 17, 2016 9:02 AM in response to marv12ca
    Level 5 (5,789 points)
    Desktops
    Sep 17, 2016 9:02 AM in response to marv12ca

    Yes, but storage space is changed a little, I suppose.

    El capitan eat up disk space around 22GB, Sierra beta is 21GB.

  • by Grant Bennet-Alder,

    Grant Bennet-Alder Grant Bennet-Alder Sep 17, 2016 9:04 AM in response to marv12ca
    Level 9 (60,951 points)
    Desktops
    Sep 17, 2016 9:04 AM in response to marv12ca

    Installing a new operating system does not bulk-erase anything, and does not just ADD all that stuff in beside your current MacOS. It selectively re-writes over 350,000 files. The new version may be slightly smaller or somewhat larger.

     

    By design, it does not disturb your files or third-party Applications. But since it is a BIG change, it would be a mistake to proceed without (at the very least) a Trusted Backup.

     

    Serious computerheads often start completely fresh and perform a drive erase (counting on TWO Trusted backups) before a major Operating System upgrade. Then restore their files from Backups.

  • by leroydouglas,

    leroydouglas leroydouglas Sep 17, 2016 9:05 AM in response to marv12ca
    Level 7 (23,578 points)
    Notebooks
    Sep 17, 2016 9:05 AM in response to marv12ca

    marv12ca wrote:

     

    When you install new operating system, will it replace old operating system without a change from its current storage space?

     

    Practically speaking, you are not going to notice a difference.

     

    Sage advice above, always have an up to date backup plan in place before a major OS upgrade. In this way you can easily fall back if need be.

     

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