Time Machine question.

Discussion in 'iMac' started by Choctaw, Sep 30, 2015.

  1. Choctaw macrumors 6502


    Apr 8, 2008
    I have searched for a correct place to post this with no results. I did not want to highjack the thread of someone else. So here I am with my question.

    Using Time Machine has not been something I participated in pryer to deciding to upgrade to El Capitan. After reading all the advise about having a secure backup before attempitng an upgrade of a new OS I decided to activate my option for TM (time machine) using and external drive. I am not pleased with the options for TM backup which lists backups as often as every hour. Ones a day or even less would be find for my not so important computer use.

    Sorry for all the writing to approach my situation. QUESTION is, if I leave the external driver that TM uses turned off during the day or even a few days. How will the backups be done when I do turn on the external hard drive?

    Thanks for your advise in this not so important matter.
  2. Alesc macrumors 6502


    Nov 11, 2014
    Hi Choctaw.
    I'm like you: I don't have the need of 1 backup per hour. So after I do some important work on my iMac, I turn the external HDD on and TM is doing the backup within the hour. You can do that when you want : once a day, once a mounth or once a year ;)
  3. Pomeroy macrumors 6502


    Sep 27, 2008
  4. Pomeroy macrumors 6502


    Sep 27, 2008
    I have been using TimeMachineEditor for years and works perfect for me. I have it update timeMachine once a week, Monday mornings at 3:00 am while I am asleep. You can set it at any interval you like and still do an update any time you want if you are updating or adding new software.
  5. chabig macrumors 603

    Sep 6, 2002
    It causes no harm to just let it run like it's designed. What exactly is your concern? Suppose you use your computer for a "not so important" task and a few hours later your HDD dies. Wouldn't it be nice to have that backup?
  6. Choctaw thread starter macrumors 6502


    Apr 8, 2008
    Pomercy......as I have stated TM is not something I know much about. When going over the settings which were not that clear as to different times it could be set to backup. I seemed to understand that the hour/day/etc were not something I could choose to use or disable. But learning more might change that for me. Contrary to the way most users do things I turn off everything at night and restart it fresh in the AM. Have been doing this for 15 years with no noted troubles. I am sure there are those who would call this an unforgivable Apple sin. But it is workable of me.
    Thanks for your input.
  7. Choctaw thread starter macrumors 6502


    Apr 8, 2008
    chabig.......my use is primarily communication, web searching and some writings which I would save to an extra drive if needed, as stated TM is designed to run and back up even on an hourly time table. For me I would only want a backup of my OS and the programs the Mac had installed on it when purchased. Yes a new HD installation would go smoother with some sort of backup. It' just a fun thing, and I am now expecting to upgrade to the new EC in a short time hopefully without any snaffles. If troubles do show their ugly faces, I will then be in the process of leaning how to use that Time Machine things to it's fullest.
    Thanks for your input and views.
  8. jordanz macrumors member


    May 13, 2012
    Pomeroy was referring to a separate piece of software called TimeMachineEditor (free). You need to download this first before you can customise the time settings like that. The standard settings without this little tool are pretty limited, yeah. Click the link in Pomercy's post and read the website's FAQ for more info. I use it myself, no complaints :)
  9. KALLT macrumors 601

    Sep 23, 2008
    Time Machine makes a complete backup of your system once. Every time it makes another it will only copy the files that have changed since your latest backup; i.e. it will record the differences. The shorter the interval, the quicker the backup. Sometimes it will only back up a few KB. Time Machine is sophisticated enough to know how your system looks at a specific point in time, even though you are not duplicating everything. It doesn’t matter if your drive is not available, because Time Machine will always attempt to just copy the difference between the last backup and now. This means that you can remove and connect your drive whenever you want. The idea behind hourly backups is that you can use the Time Machine app to restore individual files at exact moments in time. Moreover, you can manually exclude certain folders from backups in System Preferences. If you don’t want your documents backed up, just exclude the documents folder.
  10. colodane, Sep 30, 2015
    Last edited: Sep 30, 2015

    colodane macrumors 6502a


    Nov 11, 2012
    Yes, KALLT is correct. The hourly backups are nothing to be afraid of. They are almost all very small in size, correspondingly quick, and completely non-intrusive to anything else you are doing. Unless you happen to glance at the Time Machine icon you won't even realize when a backup is taking place.

    Perhaps this will make you feel better: I've been using hourly TimeMachine backups on my iMac for 4 years now. I have about 67 GB of total storage used on my Mac main SSD. The total disk space used on my TimeMachine is now 107 GB (after 4 years of hourly backups). So there is really no downside to using it this way.
  11. Choctaw thread starter macrumors 6502


    Apr 8, 2008
    Thanks all for your info concerning TM I have it up and running now.
  12. garyleecn, Oct 6, 2015
    Last edited: Oct 6, 2015

    garyleecn macrumors 6502a

    Jul 25, 2014
    im not sure what you mean you turned it off.... i assume it's the same as 'unplug' it?

    ok two things you should know.
    1. if the 1-hour period is reached, system will attempt to mount the HD and back up once, if the HD is not found, certainly it will not back up. (though i'm not sure about local backup, back in mountain lion system will back up locally first and once your HD is attached it will move the backups to the HD. and you do have option to turn it off)
    2. there are plenty apps to change the interval of backups. you can change it to whatever you like

    edit, you should also understand how TM backup works.
    'hourly' back up is not like you copy all your files over once an hour, after the initial backup, it will only copy whatever was changed/modified/added to the backup. so the size of backups will mostly be the same as 4-hour backups, with only slightly change.
    so assume you modify three files (each 1mb) every hour. and during a 4-hour interval, you've changed files like
    ABC (1st hour) DEF GAH(here you modified file A again) IJL
    so if you do hourly backup, there will be four backups, and each backup will only contain the following files
    1. ABC
    2. DEF
    3. GAH
    4. IJL
    so the size of backups will be 12mb (assuming each is 1mb)

    if you do a 4-hour backup interval, there will be only ONE backup, and contains
    the size will be 11mb, but you loose the first version of A

    so there will be two situations.
    1. you modify/reversion same files a lot.
    then the difference of backup size will vary more depending on your interval, but i think i'd rather keep more versions right?
    2. you don't reversion/modify existing files a lot
    then if you increase your backup interval, it will not save you much disk space
  13. seroposi macrumors member

    Mar 7, 2013
    Herts, UK

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12 September 30, 2015