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Transition to using 16 KB page sizes for Android apps and games

(android-developers.googleblog.com)
95 points ingve | 1 comments | 11 Jul 25 07:04 UTC | HN request time: 0s | source
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mkw5053 ◴[15 Jul 25 02:52 UTC] No.44567439[source]▶
I used to work closely with the Android team at Unity, and in my experience, shifting large native codebases to a new page size often uncovers subtle runtime assumptions beyond just replacing hardcoded constants like PAGE_SIZE. I’m optimistic Google’s tooling will help a lot, but interested about how effectively it catches these more nuanced compatibility issues like custom allocators or memory pooling tuned for 4K boundaries.
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HPsquared ◴[15 Jul 25 06:47 UTC] No.44568557[source]▶
Could they find those by setting page size to some absurdly large value like 1MB?
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majke ◴[15 Jul 25 07:59 UTC] No.44568979[source]▶
A lot of software wont work if you do that. Many jits and memory allocators have opinions on page size. Also tagged pointers are very common.
replies(3): >>44569427 #>>44571507 #>>44572184 #
1. bigstrat2003 ◴[15 Jul 25 14:28 UTC] No.44571507[source]▶
This just provides yet another example of why tagged pointers are a terrible idea and shouldn't be used. Someday, more of the address space will get used and your software will break.