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A comment on AMD Claims Arm ISA Doesn't Offer Efficiency Advantage over x86. Parent comment

Re:AMD Claims Arm ISA Doesn't Offer Efficiency Advantage ove... by adgjlsfhk1 on Monday September 08, 2025 @08:23PM (#45175887)
> - The hardcoded page size.

I'm pretty confident that this will get removed. It's an extension that made it's way into RVA23, but once anyone has a design big enough for it to be a burden, it can be dropped.

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Re:AMD Claims Arm ISA Doesn't Offer Efficiency Advantage ove... by monocasa on Monday September 08, 2025 @11:09PM (#45176947)
That's really hard to drop.

Fancier unix programs tend to make all kinds of assumptions about page size to do things like the double mapped ring buffer trick.

https://en.wikipedia.org/wiki/Circular_buffer#Optimization

In fact it looks like apple silicon maintains support for 4kb pages just for running Rosetta. It's one of those things like TSO that was enough of a pain to work around the assumptions that they just included hardware support for it that isn't enabled when running in regular arm software mode.

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