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A comment on Raspberry Pi OS 32-bit vs. 64-bit Performance.

Re:Raspberry Pi OS 32-bit vs. 64-bit Performance by diimdeep on Monday February 07, 2022 @01:22PM (#30248854)
> Using a 64-bit kernel (arm_64bit=1) just takes away 50MB of RAM, the worst choice is to combine 64-bit kernel and 64-bit userland since everything relevant get slower, same tasks require much more memory and the device will start to swap if low on memory or even kill processes due to out of memory.

> As a rule of thumb you need almost twice as much RAM with a 64-bit userland compared to 32-bit with the same programs/services running. [1]

[1]: https://github.com/ThomasKaiser/sbc-bench/blob/master/Result...

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Re:Raspberry Pi OS 32-bit vs. 64-bit Performance by viraptor on Monday February 07, 2022 @03:43PM (#30250788)
That's not supported by any data posted there. You'd have to have almost all of your memory filled will pointers to achieve 2x increase which just doesn't happen in reality. Looking at a large application like Firefox https://www.raymond.cc/blog/mozilla-firefox-64bit-build-perf... you get ~30% increase.
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Re:Raspberry Pi OS 32-bit vs. 64-bit Performance by yjftsjthsd-h on Monday February 07, 2022 @06:15PM (#30252852)
>> As a rule of thumb you need almost twice as much RAM with a 64-bit userland compared to 32-bit with the same programs/services running.

That doesn't make sense; going 64-bit should only double the size of pointers, it shouldn't touch the size of code or data in memory.

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