iPhone XS Storage Space Question

mjschabow

macrumors 68030
Original poster
Dec 25, 2013
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Hi all. Very random question but something I’ve always wondered. If I were to almost fill my entire hard drive space up (I have the 256gb so probably would never happen) how much space do I really need left on my device to avoid slowdowns. I’ve always tried to leave a lot of remaining space but I know someone who always leaves about 2gb left and that’s it. Just overall curious if there are any rules of thumb when it comes to how much space to leave open.
 

now i see it

macrumors 601
Jan 2, 2002
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well to put things in perspective, Apple sold untold millions of iPhones in the past with only 16GB of storage. You can bet none of those poor unlucky souls had much empty space remaining on them. 2GB would be a luxury (and plenty).

Personally on my 64GB iPhone I like to keep at least 10GB free, not so much for potential speed improvements, but to give me room to record a big video or download a big file
 
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MacCheetah3

macrumors 6502
Nov 14, 2003
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From my own experience and others’ reports, you’ll want to keep at least 25% storage space free. When it’s less than 10% I/O efficiency will probably suffer significantly.
 
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lordofthereef

macrumors G5
Nov 29, 2011
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I can't speak for more than just my experiences. But family members had 26gb phones for ages (and in always the one serving things up). They easily filled them miserly and they didn't experience slowdown.

My son still has a 16gb SE that I use from time to time and I see no issues.

Obviously no scientific tests whatsoever. But if I haven't noticed a slow down with s couple hundred Megs left on s 26gb phone I'm certainly not going to stress, personally.
 
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MacCheetah3

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Nov 14, 2003
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I can speak for more than just my experiences. But family members had 26gb phones for ages (and in always the one serving things up). They easily filled them miserly and they didn't experience slowdown.

My son still has a 16gb SE that I use from time to time and I see no issues.

Obviously no scientific tests whatsoever. But if I haven't noticed a slow down with s couple hundred Megs left on s 26gb phone I'm certainly not going to stress, personally.
I assume, "mileage may vary" as some say because of so many factors. But to elaborate a bit, my iPad 2 32GB had similar behaviors to this:

https://forums.macrumors.com/threads/how-much-freespace-is-optimal-for-ipad-performance.1436736/#post-15623088

Even if iOS doesn't utilize paging files (i.e., virtual memory), individual apps, such as Web browsers, often do have their own data caching, which, of course, may require additional storage space and will need to perform extra duties if none is available. Lastly, that doesn't even account for swapping resources during app/OS updates, etc.
 

lordofthereef

macrumors G5
Nov 29, 2011
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Boston, MA
I assume, "mileage may vary" as some say because of so many factors. But to elaborate a bit, my iPad 2 32GB had similar behaviors to this:

https://forums.macrumors.com/threads/how-much-freespace-is-optimal-for-ipad-performance.1436736/#post-15623088

Even if iOS doesn't utilize paging files (i.e., virtual memory), individual apps, such as Web browsers, often do have their own data caching, which, of course, may require additional storage space and will need to perform extra duties if none is available. Lastly, that doesn't even account for swapping resources during app/OS updates, etc.
I'm not sure why you're quoting me here unless it's because of my typo "I can" shouldn't read "I can't". I haven't experienced any of the issues in that thread, but I haven't done any extensive testing. I suppose it's also possible I'm not using it enough to notice anything.

My son uses the SE and doesn't web browse but does play games, a lot of Pokémon go, plays music, etc. he hasn't reported any crashing whatsoever.

If there's a specific test I can run I'm happy to try it.
 

MacCheetah3

macrumors 6502
Nov 14, 2003
445
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I'm not sure why you're quoting me here unless it's because of my typo "I can" shouldn't read "I can't". I haven't experienced any of the issues in that thread, but I haven't done any extensive testing. I suppose it's also possible I'm not using it enough to notice anything.

My son uses the SE and doesn't web browse but does play games, a lot of Pokémon go, plays music, etc. he hasn't reported any crashing whatsoever.

If there's a specific test I can run I'm happy to try it.
My point is simply that even though you haven’t seen any affect/correlation between (lack of) free storage space amount and performance/reliability, some have. And at least some technical arguments exist highlighting the legit possibility Therefore, presumably, it’s a situation that’s worth putting some effort in to avoid. No?
 

lordofthereef

macrumors G5
Nov 29, 2011
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My point is simply that even though you haven’t seen any affect/correlation between (lack of) free storage space amount and performance/reliability, some have. And at least some technical arguments exist highlighting the legit possibility Therefore, presumably, it’s a situation that’s worth putting some effort in to avoid. No?
I wasn't trying to state that it's not an issue. I was simply sharing my own experience, my friend.

You're not wrong and I never implied you were.
 

MacCheetah3

macrumors 6502
Nov 14, 2003
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Sauk Rapids, MN
I wasn't trying to state that it's not an issue. I was simply sharing my own experience, my friend.

You're not wrong and I never implied you were.
I think, miscommunication. I also wasn't intending to argue with your point. I have no reason to doubt you didn't witness the same effects I did in regard to the topic.

Looking back, I probably should've just done a simple reply without quote, it likely would've been less confusing/confronting. It was meant to highlight why we may have conflicting experiences.

Anywho... Hope we're good now. :)
 
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lordofthereef

macrumors G5
Nov 29, 2011
12,871
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Boston, MA
I think, miscommunication. I also wasn't intending to argue with your point. I have no reason to doubt you didn't witness the same effects I did in regard to the topic.

Looking back, I probably should've just done a simple reply without quote, it likely would've been less confusing/confronting. It was meant to highlight why we may have conflicting experiences.

Anywho... Hope we're good now. :)
No worries at all. I probably came off as more defensive than I really was. I honestly first assumed my stupid typos were the reason you responded directly to me lol.
 

rui no onna

macrumors 604
Oct 25, 2013
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So 2GB storage, 500GB needed to maintain performance. Got it.
I'm guessing you meant 2TB? In fairness, there are actually SSDs with 100% OP for very write intensive tasks. How much space to leave free all depends on workload.

iOS likes to have 10% free, I believe. I have iCloud Photo Library set to "Download and Keep Originals" and it stops syncing and starts complaining about insufficient space and tells me to switch to "Optimize iPad Storage" if free space goes below 10%.