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by kuhsaft 620 days ago
That's memory mapping. This is memory paging [1]. I.e. Windows pagefile.sys, Linux swap, macOS swap files. iOS does not have swap files, only memory compression. If you're on a Mac, open up Activity Monitor, go to Memory, and at the bottom there is `Swap Used`. That doesn't exist on iOS. So, if more memory is used than available, applications will need to free memory or be terminated. Unlike macOS, where some used memory will be swapped to disk to allow other stuff to be loaded into memory.

[1] https://en.wikipedia.org/wiki/Memory_paging
1 comments
Rohansi 620 days ago
It's most likely just disabled rather than being completely different/non-existent. But yes, the application model is built around limited to no multitasking.
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kuhsaft 620 days ago
> It's most likely just disabled rather than being completely different/non-existent.

As evident by the limited Virtual Memory Swap enabled on iPadOS 16, but not iOS.

All Apple devices use the XNU kernel. But, as the parent blog post shows, the kernel configuration, device tree, and drivers are different.

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