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I'm asking if TRIM is enabled on iOS because, ever since I ran out of memory on my iPhone (have since cleared a few GB back), it seems to be slower than it was before. My suspicion being that, with most flash memory "sectors" now partially used, every write operation now takes longer…

Relying heavily on flash memory, I wonder if the iPhone implements TRIM (or any "trim-like" feature) to maximize flash memory performance and specifically if that will let me troubleshoot a slow phone and/or know if I would want to jailbreak the device to enable TRIM or otherwise control storage more tightly than iOS is delivered.

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migrated from Feb 16 '11 at 11:36

This question came from our site for computer enthusiasts and power users.

I've removed the second part of your question because this can't really be answered here. – patrix Jul 29 '13 at 13:00
I still have no ideia if iOS implements (or will implement) TRIM support in the future, but at least for Android - although it took them a while - it's coming with the new Android 4.3 TRIM support. (I imagine iOS won't be far behind in doing so, if it doesn't already.) – ptnik Jul 30 '13 at 10:13
I see two reasons to open this, but I don't know which question you really have: 1) Yes or no - is there trim on iOS in general 2) How do I diagnose a slow phone whether or not it has TRIM. Since we prefer questions that are practical and discourage yes/no ones, I'll edit this assuming you really want to know #2 - anyone is free to edit this again and we can review / close again should it get too broad or unfocused down the line. – bmike Jul 30 '13 at 13:12

Since I'm just a generic curious who can do some research on the web, I'll make here some assumptions so we can be on the same grounds:

  • TRIM is an SSD technology and, as such, can mean too many different things.
  • iPhone uses MLC NAND memory, which is indeed a SSD.
  • We, people, (such as dhy8386 and maybe even Mr. Brian Klug) love to talk big about things we don't know deep enough. To know more, trust less.
  • Apple mostly does not disclose anything technically meaningful about their technology. And it does use many proprietary technologies nobody else does.
  • Even today, the iPhone will work way more flawlessly under deep stress (filled memory, many applications, etc) than any Android or Windows Phone. (yes, I've used them all and I currently own a S3)

If you follow every link above deep enough, you may realize it's just not that simple. Even Android's TRIM support probably isn't the same TRIM as a notebook uses on its SSD.

So, it doesn't matter if it supports TRIM or not. The whole point of going with an iPhone is trusting Apple and letting them do the hardcore tech work. And the whole point of jailbreaking is being able to do things Apple can't allow for any reason, such as unblocking carriers. Anything else on JB is doing it wrong (specially now we have android, even for iPhone) - and I'm saying that from my heavy experience using jailbreak from iPhone 3 to 4.

Now, to address your main and unannounced question, best thing you can do to test if your hardware is malfunctioning is to backup your iPhone and reset to factory. Then fill it up with music or pictures, since you suspect a full disk is causing the malfunctioning, and avoid installing applications at all. You probably won't see any problem and, if you do, just send it to warranty. You can also send it to warranty directly, but you risk of it coming back and just losing few days there.

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I don't understand why you make the assumption the device is a jailbreak device. The asker never indicated that, and I arrived at this question because I suspected my iPhone could have the very problem. My iPhone has never been jailbroken ... not even once. As for the difference between SSD and RAM, I don't see how that's relevant. I/O plays a critical role in system performance. If the SSD is slowing down, then the user will see a noticeable impact on performance. – Avian00 Jul 29 '13 at 7:44
@Avian00 because, back then, iPhone didn't have multitasking. It would be very difficult to load the memory up without having jailbreak (to allow multitasking). As for performance, I'll edit the question to add few points and updates that happened since then. – cregox Jul 29 '13 at 10:41
@Cawas My question had nothing to do with available RAM or multitasking, but with the performance of the flash storage subsystem before/after it had been completely filled up. You'd get decent performance in one case, it would get worse after filling it up and freeing it again. In Android, Google brought TRIM support to the Nexus in the latest 4.3 (took them long enough! :) I wonder if/when Apple does the same in iOS. – ptnik Jul 30 '13 at 10:36
@Cawas Why the heck do you mix it up with RAM?? – Max Ried Jul 30 '13 at 12:12
Interestingly Android 4.3 was the first Android to support TRIM on certain devices. I doubt iOS supports TRIM. – Max Ried Jul 30 '13 at 12:14

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